CWE-116
Allowed-with-ReviewImproper Encoding or Escaping of Output
Abstraction: Class · Status: Draft
The product prepares a structured message for communication with another component, but encoding or escaping of the data is either missing or done incorrectly. As a result, the intended structure of the message is not preserved.
705 vulnerabilities reference this CWE, most recent first.
GHSA-FW4X-J9WF-QMP2
Vulnerability from github – Published: 2025-03-21 06:30 – Updated: 2025-03-21 06:30An issue was discovered in OpenSlides before 4.2.5. When creating new chats via the chat_group.create action, the user is able to specify the name of the chat. Some HTML elements such as SCRIPT are filtered, whereas others are not. In most cases, HTML entities are encoded properly, but not when deleting chats or deleting messages in these chats. This potentially allows attackers to interfere with the layout of the rendered website, but it is unlikely that victims would click on deleted chats or deleted messages.
{
"affected": [],
"aliases": [
"CVE-2025-30345"
],
"database_specific": {
"cwe_ids": [
"CWE-116",
"CWE-79"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2025-03-21T06:15:27Z",
"severity": "LOW"
},
"details": "An issue was discovered in OpenSlides before 4.2.5. When creating new chats via the chat_group.create action, the user is able to specify the name of the chat. Some HTML elements such as SCRIPT are filtered, whereas others are not. In most cases, HTML entities are encoded properly, but not when deleting chats or deleting messages in these chats. This potentially allows attackers to interfere with the layout of the rendered website, but it is unlikely that victims would click on deleted chats or deleted messages.",
"id": "GHSA-fw4x-j9wf-qmp2",
"modified": "2025-03-21T06:30:28Z",
"published": "2025-03-21T06:30:27Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-30345"
},
{
"type": "WEB",
"url": "https://www.x41-dsec.de/lab/advisories/x41-2025-001-OpenSlides"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N",
"type": "CVSS_V3"
}
]
}
GHSA-FW85-97W2-FP5V
Vulnerability from github – Published: 2022-05-24 17:42 – Updated: 2022-05-24 17:42Improper Encoding or Escaping of Output from CSV Report Generator of Secomea GateManager allows an authenticated administrator to generate a CSV file that may run arbitrary commands on a victim's computer when opened in a spreadsheet program (like Excel). This issue affects: Secomea GateManager all versions prior to 9.3.
{
"affected": [],
"aliases": [
"CVE-2020-29023"
],
"database_specific": {
"cwe_ids": [
"CWE-116"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2021-02-16T16:15:00Z",
"severity": "MODERATE"
},
"details": "Improper Encoding or Escaping of Output from CSV Report Generator of Secomea GateManager allows an authenticated administrator to generate a CSV file that may run arbitrary commands on a victim\u0027s computer when opened in a spreadsheet program (like Excel). This issue affects: Secomea GateManager all versions prior to 9.3.",
"id": "GHSA-fw85-97w2-fp5v",
"modified": "2022-05-24T17:42:18Z",
"published": "2022-05-24T17:42:18Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2020-29023"
},
{
"type": "WEB",
"url": "https://www.secomea.com/support/cybersecurity-advisory"
},
{
"type": "WEB",
"url": "https://www.secomea.com/support/cybersecurity-advisory/#2418"
}
],
"schema_version": "1.4.0",
"severity": []
}
GHSA-FWHG-JHXM-42V5
Vulnerability from github – Published: 2025-08-27 00:31 – Updated: 2025-08-27 15:33In multiple locations, there is a possible way to access content across user profiles due to URI double encoding. This could lead to local information disclosure with no additional execution privileges needed. User interaction is not needed for exploitation.
{
"affected": [],
"aliases": [
"CVE-2025-0083"
],
"database_specific": {
"cwe_ids": [
"CWE-116"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2025-08-26T23:15:32Z",
"severity": "MODERATE"
},
"details": "In multiple locations, there is a possible way to access content across user profiles due to URI double encoding. This could lead to local information disclosure with no additional execution privileges needed. User interaction is not needed for exploitation.",
"id": "GHSA-fwhg-jhxm-42v5",
"modified": "2025-08-27T15:33:14Z",
"published": "2025-08-27T00:31:15Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-0083"
},
{
"type": "WEB",
"url": "https://android.googlesource.com/platform/frameworks/base/+/7ba8c8f63f1b13b127c871749314a242ff022ae2"
},
{
"type": "WEB",
"url": "https://android.googlesource.com/platform/packages/services/Telecomm/+/685c2fc2f6b40bb2113db77da270c7b7220791c4"
},
{
"type": "WEB",
"url": "https://source.android.com/security/bulletin/2025-03-01"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N",
"type": "CVSS_V3"
}
]
}
GHSA-FXGQ-9M89-CXJ9
Vulnerability from github – Published: 2026-08-25 18:23 – Updated: 2026-08-25 18:23Summary
eml_parser performs certain validations on potential URL strings to discard bogus values. In versions prior to 3.0.2, this validation was performed before unescaping any HTML entities that might occur in the string. This caused the library to wrongfully reject valid URLs that use HTML entities for the :, /, or . characters. These URLs would then not be included in the list of extracted URLs. Similarly, the host parts of such URLs would not be extracted.
For example, neither the URL https://phishing.example.com nor its host (phishing.example.com) would appear in the parsing result.
Impact
eml_parser is used in email security gateways and SOC pipelines to extract URLs as IOCs. Those URLs are then checked against threat-intel feeds, URL reputation services, and sandboxes. A URL that is not extracted is never checked.
Patches
Since version 3.0.2 the library unescapes all HTML entities in every URL before deciding to accept or reject it. A test was added to prevent regressions.
{
"affected": [
{
"package": {
"ecosystem": "PyPI",
"name": "eml_parser"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "3.0.2"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2026-55618"
],
"database_specific": {
"cwe_ids": [
"CWE-116"
],
"github_reviewed": true,
"github_reviewed_at": "2026-08-25T18:23:16Z",
"nvd_published_at": null,
"severity": "MODERATE"
},
"details": "## Summary\n\n`eml_parser` performs certain validations on potential URL strings to discard bogus values. In versions prior to `3.0.2`, this validation was performed before unescaping any HTML entities that might occur in the string. This caused the library to wrongfully reject valid URLs that use HTML entities for the `:`, `/`, or `.` characters. These URLs would then not be included in the list of extracted URLs. Similarly, the host parts of such URLs would not be extracted.\n\nFor example, neither the URL `https\u0026#58;\u0026#47;\u0026#47;phishing\u0026#46;example\u0026#46;com` nor its host (`phishing.example.com`) would appear in the parsing result.\n\n## Impact\n\n`eml_parser` is used in email security gateways and SOC pipelines to extract URLs as IOCs. Those URLs are then checked against threat-intel feeds, URL reputation services, and sandboxes. A URL that is not extracted is never checked.\n\n## Patches\n\nSince version 3.0.2 the library unescapes all HTML entities in every URL before deciding to accept or reject it. A test was added to prevent regressions.",
"id": "GHSA-fxgq-9m89-cxj9",
"modified": "2026-08-25T18:23:16Z",
"published": "2026-08-25T18:23:16Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/GOVCERT-LU/eml_parser/security/advisories/GHSA-fxgq-9m89-cxj9"
},
{
"type": "WEB",
"url": "https://github.com/GOVCERT-LU/eml_parser/pull/90"
},
{
"type": "WEB",
"url": "https://github.com/GOVCERT-LU/eml_parser/commit/746a69f86443eb0b6a47f77db3cfe727c21f92b3"
},
{
"type": "PACKAGE",
"url": "https://github.com/GOVCERT-LU/eml_parser"
},
{
"type": "WEB",
"url": "https://github.com/GOVCERT-LU/eml_parser/releases/tag/v3.0.2"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N",
"type": "CVSS_V3"
}
],
"summary": "eml_parser has a URL extraction bypass via HTML entities in URLs"
}
GHSA-G2G4-47GV-P72V
Vulnerability from github – Published: 2026-05-26 19:05 – Updated: 2026-05-26 19:05Summary
CryptPad’s HTML sanitizer in Diffmarked.js can be bypassed due to incomplete filtering of restricted tags.
Because the sanitizer only validates the src attribute of <iframe> <video>, and <audio> elements, and does not restrict other attributes, an attacker can inject arbitrary HTML through srcdoc. This completely defeats CryptPad’s intended bounce sandboxing and allows link injection or other interactive content inside user-controlled documents.
Details
The sanitizer defines forbidden and restricted tags but treats as “restricted” instead of “forbidden”:
https://github.com/cryptpad/cryptpad/blob/0dd3c1f53d56dffb06651b86ead6b9b387920173/www/common/diffMarked.js#L403-L407 The actual enforcement only checks the src attribute, nothing else:
https://github.com/cryptpad/cryptpad/blob/0dd3c1f53d56dffb06651b86ead6b9b387920173/www/common/diffMarked.js#L445-L449
Because only src is validated, adding a benign blob: src but malicious srcdoc results in unrestricted rendering.
PoC
An attacker can embed arbitrary HTML, including clickable external links, images, or interactive content, completely bypassing CryptPad’s bounce mechanism and sanitization:
<iframe src=blob: srcdoc="<a href=https://attacker.com target=_blank>CLICK ME</a>"></iframe>
Although CSP is strict, CryptPad exposes several same-origin gadgets that can execute attacker-controlled code.
For example, jscolor.js dynamically evaluates user-provided options:
https://github.com/cryptpad/cryptpad/blob/0dd3c1f53d56dffb06651b86ead6b9b387920173/www/common/jscolor.js#L65-L71
Impact
Sanitizer bypass, HTML injection and potentially XSS.
{
"affected": [
{
"package": {
"ecosystem": "npm",
"name": "cryptpad"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"last_affected": "5.9.0"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2026-26028"
],
"database_specific": {
"cwe_ids": [
"CWE-116",
"CWE-79"
],
"github_reviewed": true,
"github_reviewed_at": "2026-05-26T19:05:10Z",
"nvd_published_at": "2026-05-20T20:16:36Z",
"severity": "MODERATE"
},
"details": "### Summary\nCryptPad\u2019s HTML sanitizer in Diffmarked.js can be bypassed due to incomplete filtering of restricted tags.\nBecause the sanitizer only validates the src attribute of `\u003ciframe\u003e` `\u003cvideo\u003e`, and `\u003caudio\u003e` elements, and does not restrict other attributes, an attacker can inject arbitrary HTML through srcdoc. This completely defeats CryptPad\u2019s intended bounce sandboxing and allows link injection or other interactive content inside user-controlled documents.\n\n### Details\nThe sanitizer defines forbidden and restricted tags but treats \u003ciframe\u003e as \u201crestricted\u201d instead of \u201cforbidden\u201d:\n\nhttps://github.com/cryptpad/cryptpad/blob/0dd3c1f53d56dffb06651b86ead6b9b387920173/www/common/diffMarked.js#L403-L407\nThe actual enforcement only checks the src attribute, nothing else:\n\nhttps://github.com/cryptpad/cryptpad/blob/0dd3c1f53d56dffb06651b86ead6b9b387920173/www/common/diffMarked.js#L445-L449\n\nBecause only src is validated, adding a benign blob: src but malicious srcdoc results in unrestricted rendering.\n### PoC\n\nAn attacker can embed arbitrary HTML, including clickable external links, images, or interactive content, completely bypassing CryptPad\u2019s bounce mechanism and sanitization:\n\n```html\n\u003ciframe src=blob: srcdoc=\"\u003ca href=https://attacker.com target=_blank\u003eCLICK ME\u003c/a\u003e\"\u003e\u003c/iframe\u003e\n```\n\nAlthough CSP is strict, CryptPad exposes several same-origin gadgets that can execute attacker-controlled code.\n\nFor example, `jscolor.js` dynamically evaluates user-provided options:\nhttps://github.com/cryptpad/cryptpad/blob/0dd3c1f53d56dffb06651b86ead6b9b387920173/www/common/jscolor.js#L65-L71\n\n### Impact\nSanitizer bypass, HTML injection and potentially XSS.",
"id": "GHSA-g2g4-47gv-p72v",
"modified": "2026-05-26T19:05:10Z",
"published": "2026-05-26T19:05:10Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/cryptpad/cryptpad/security/advisories/GHSA-g2g4-47gv-p72v"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-26028"
},
{
"type": "PACKAGE",
"url": "https://github.com/cryptpad/cryptpad"
},
{
"type": "WEB",
"url": "https://github.com/cryptpad/cryptpad/releases/tag/2026.2.0"
}
],
"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": "CryptPad has a Sanitizer Bypass in Diffmarked.js that Allows Arbitrary HTML Injection and Potential XSS"
}
GHSA-G2VG-8HFG-79VJ
Vulnerability from github – Published: 2024-12-24 06:30 – Updated: 2025-02-07 06:31A vulnerability in Koji was found. An unsanitized input allows for an XSS attack. Javascript code from a malicious link could be reflected in the resulting web page. It is not expected to be able to submit an action or make a change in Koji due to existing XSS protections in the code.
{
"affected": [
{
"package": {
"ecosystem": "PyPI",
"name": "koji"
},
"ranges": [
{
"events": [
{
"introduced": "1.35.0"
},
{
"fixed": "1.35.1"
}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"1.35.0"
]
},
{
"package": {
"ecosystem": "PyPI",
"name": "koji"
},
"ranges": [
{
"events": [
{
"introduced": "1.34.0"
},
{
"fixed": "1.34.3"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "PyPI",
"name": "koji"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "1.33.2"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2024-9427"
],
"database_specific": {
"cwe_ids": [
"CWE-116"
],
"github_reviewed": true,
"github_reviewed_at": "2024-12-26T20:22:34Z",
"nvd_published_at": "2024-12-24T04:15:07Z",
"severity": "MODERATE"
},
"details": "A vulnerability in Koji was found. An unsanitized input allows for an XSS attack. Javascript code from a malicious link could be reflected in the resulting web page. It is not expected to be able to submit an action or make a change in Koji due to existing XSS protections in the code.",
"id": "GHSA-g2vg-8hfg-79vj",
"modified": "2025-02-07T06:31:13Z",
"published": "2024-12-24T06:30:42Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2024-9427"
},
{
"type": "WEB",
"url": "https://access.redhat.com/security/cve/CVE-2024-9427"
},
{
"type": "WEB",
"url": "https://bugzilla.redhat.com/show_bug.cgi?id=2316047"
},
{
"type": "WEB",
"url": "https://docs.pagure.org/koji/CVEs/CVE-2024-9427"
},
{
"type": "PACKAGE",
"url": "https://pagure.io/koji"
},
{
"type": "WEB",
"url": "https://pagure.io/koji/c/8c72d90d7bb991f8fb193851b80847ac9e9474a4?branch=master"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N",
"type": "CVSS_V3"
}
],
"summary": "Koji Cross-site Scripting"
}
GHSA-G4PX-P74V-Q4C7
Vulnerability from github – Published: 2022-05-24 19:11 – Updated: 2022-05-24 19:11Under very specific conditions a user could be impersonated using Gitlab shell. This vulnerability affects GitLab CE/EE 13.1 and later through 14.1.2, 14.0.7 and 13.12.9.
{
"affected": [],
"aliases": [
"CVE-2021-22254"
],
"database_specific": {
"cwe_ids": [
"CWE-116"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2021-08-20T18:15:00Z",
"severity": "MODERATE"
},
"details": "Under very specific conditions a user could be impersonated using Gitlab shell. This vulnerability affects GitLab CE/EE 13.1 and later through 14.1.2, 14.0.7 and 13.12.9.",
"id": "GHSA-g4px-p74v-q4c7",
"modified": "2022-05-24T19:11:48Z",
"published": "2022-05-24T19:11:48Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2021-22254"
},
{
"type": "WEB",
"url": "https://hackerone.com/reports/1087806"
},
{
"type": "WEB",
"url": "https://gitlab.com/gitlab-org/cves/-/blob/master/2021/CVE-2021-22254.json"
},
{
"type": "WEB",
"url": "https://gitlab.com/gitlab-org/gitlab/-/issues/300265"
}
],
"schema_version": "1.4.0",
"severity": []
}
GHSA-G4VP-M682-QQMP
Vulnerability from github – Published: 2023-08-11 19:00 – Updated: 2023-08-11 19:00Impact
OpenZeppelin Contracts is a library for secure smart contract development. Starting in version 4.0.0 and prior to version 4.9.3, contracts using ERC2771Context along with a custom trusted forwarder may see _msgSender return address(0) in calls that originate from the forwarder with calldata shorter than 20 bytes. This combination of circumstances does not appear to be common, in particular it is not the case for MinimalForwarder from OpenZeppelin Contracts, or any deployed forwarder the team is aware of, given that the signer address is appended to all calls that originate from these forwarders.
Patches
The problem has been patched in v4.9.3.
{
"affected": [
{
"package": {
"ecosystem": "npm",
"name": "@openzeppelin/contracts"
},
"ranges": [
{
"events": [
{
"introduced": "4.0.0"
},
{
"fixed": "4.9.3"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "npm",
"name": "@openzeppelin/contracts-upgradeable"
},
"ranges": [
{
"events": [
{
"introduced": "4.0.0"
},
{
"fixed": "4.9.3"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2023-40014"
],
"database_specific": {
"cwe_ids": [
"CWE-116"
],
"github_reviewed": true,
"github_reviewed_at": "2023-08-11T19:00:48Z",
"nvd_published_at": "2023-08-10T20:15:10Z",
"severity": "MODERATE"
},
"details": "### Impact\n\nOpenZeppelin Contracts is a library for secure smart contract development. Starting in version 4.0.0 and prior to version 4.9.3, contracts using `ERC2771Context` along with a custom trusted forwarder may see `_msgSender` return `address(0)` in calls that originate from the forwarder with calldata shorter than 20 bytes. This combination of circumstances does not appear to be common, in particular it is not the case for `MinimalForwarder` from OpenZeppelin Contracts, or any deployed forwarder the team is aware of, given that the signer address is appended to all calls that originate from these forwarders.\n\n### Patches\n\nThe problem has been patched in v4.9.3.\n",
"id": "GHSA-g4vp-m682-qqmp",
"modified": "2023-08-11T19:00:48Z",
"published": "2023-08-11T19:00:48Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/OpenZeppelin/openzeppelin-contracts/security/advisories/GHSA-g4vp-m682-qqmp"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2023-40014"
},
{
"type": "WEB",
"url": "https://github.com/OpenZeppelin/openzeppelin-contracts/pull/4481"
},
{
"type": "WEB",
"url": "https://github.com/OpenZeppelin/openzeppelin-contracts/pull/4484"
},
{
"type": "WEB",
"url": "https://github.com/OpenZeppelin/openzeppelin-contracts/commit/9445f96223041abf2bf08daa56f8da50b674cbcd"
},
{
"type": "WEB",
"url": "https://github.com/OpenZeppelin/openzeppelin-contracts/commit/e4435eed757d4309436b1e06608e97b6d6e2fdb5"
},
{
"type": "PACKAGE",
"url": "https://github.com/OpenZeppelin/openzeppelin-contracts"
},
{
"type": "WEB",
"url": "https://github.com/OpenZeppelin/openzeppelin-contracts/blob/v4.9.3/CHANGELOG.md"
},
{
"type": "WEB",
"url": "https://github.com/OpenZeppelin/openzeppelin-contracts/releases/tag/v4.9.3"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N",
"type": "CVSS_V3"
}
],
"summary": "OpenZeppelin Contracts vulnerable to Improper Escaping of Output"
}
GHSA-G5M9-Q65C-X6M4
Vulnerability from github – Published: 2024-06-06 09:30 – Updated: 2024-06-11 18:30A host whitelist parser issue in the proxy service implemented in the GravityZone Update Server allows an attacker to cause a server-side request forgery. This issue only affects GravityZone Console versions before 6.38.1-2 that are running only on premise.
{
"affected": [],
"aliases": [
"CVE-2024-4177"
],
"database_specific": {
"cwe_ids": [
"CWE-116",
"CWE-918"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2024-06-06T08:15:39Z",
"severity": "HIGH"
},
"details": "A host whitelist parser issue in the proxy service implemented in the GravityZone Update Server allows an attacker to cause a server-side request forgery. This issue only affects GravityZone Console versions before 6.38.1-2 that are running only on premise.",
"id": "GHSA-g5m9-q65c-x6m4",
"modified": "2024-06-11T18:30:43Z",
"published": "2024-06-06T09:30:51Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2024-4177"
},
{
"type": "WEB",
"url": "https://bitdefender.com/consumer/support/support/security-advisories/host-whitelist-parser-issue-in-gravityzone-console-on-premise-va-11554"
},
{
"type": "WEB",
"url": "https://www.cve.org/CVERecord?id=CVE-2024-4177"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-G5XC-5W98-JFVM
Vulnerability from github – Published: 2026-08-28 22:53 – Updated: 2026-08-28 22:53Summary
A SQL injection is possible when the connector escapes Buffer parameters client-side under a multi-byte client character set whose trail-byte range overlaps the ASCII backslash (0x5C): big5, gbk, sjis, cp932, and gb18030. Under these charsets, an attacker-controlled lead byte can absorb the escape byte the connector inserts, leaving the following quote unescaped so it terminates the string literal and injected SQL is parsed.
Details
When binding a Buffer (binary) parameter, the connector escapes the value byte-by-byte, inserting a backslash (0x5C) before quote (0x27) and backslash bytes. This is correct under single-byte and UTF-8–family charsets, but unsafe under client charsets whose multi-byte trail-byte range includes 0x5C.
On the server, the SQL lexer performs multi-byte character recognition (my_ismbchar) before it interprets escape sequences. If character_set_client is one of the affected charsets and the attacker controls a byte the lexer treats as a valid lead byte, the sequence <0x5C> is consumed as a single multi-byte character. The escaping backslash inserted by the connector is swallowed as that character's trail byte, so the following 0x27 is no longer escaped — it closes the string literal, and the remaining bytes are parsed as SQL.
This is the well-known multi-byte escaping bypass (the same class that historically affected addslashes / mysql_real_escape_string under GBK/Big5), here applied to the connector's client-side Buffer escaping path.
Am I affected?
You are affected if all of the following hold:
You use mariadb Connector/Node.js at a version below the patched releases listed below. The connection's client character set is one of big5, gbk, sjis, cp932, or gb18030. This is not the default (the default is utf8mb4). Untrusted data can reach a Buffer-typed query parameter.
Applications using utf8mb4 (or any charset whose trail-byte range does not include 0x5C) are not affected by this vector. Parameters bound through the binary/server-side prepared-statement path are also not affected, because those values are sent out-of-band and are never escaped into the SQL text.
Impact
SQL injection. An attacker able to influence the contents of a Buffer parameter can break out of the intended string literal and inject arbitrary SQL, leading to unauthorized read or modification of data and, depending on the database account's privileges, further compromise.
Patches
Fixed in 3.2.4, 3.3.3, 3.4.6, and 3.5.3. Upgrade to the patched release on your branch:
- 3.5.x → 3.5.3
- 3.4.x → 3.4.6
- 3.3.x → 3.3.3
- 3.2.x and earlier → 3.2.4 (or any newer release)
Workarounds
If you cannot upgrade immediately:
Use server-side prepared statements (execute) so parameters are bound via the binary protocol rather than escaped into the SQL text. Avoid passing untrusted data as Buffer parameters under the affected charsets.
Credit
Reported by Yalguun Tumenkhuu (@fg0x0).
{
"affected": [
{
"package": {
"ecosystem": "npm",
"name": "mariadb"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "3.2.4"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"database_specific": {
"last_known_affected_version_range": "\u003c 3.3.3"
},
"package": {
"ecosystem": "npm",
"name": "mariadb"
},
"ranges": [
{
"events": [
{
"introduced": "3.3.0"
},
{
"fixed": "3.3.4"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "npm",
"name": "mariadb"
},
"ranges": [
{
"events": [
{
"introduced": "3.4.0"
},
{
"fixed": "3.4.6"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "npm",
"name": "mariadb"
},
"ranges": [
{
"events": [
{
"introduced": "3.5.0"
},
{
"fixed": "3.5.3"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2026-55855"
],
"database_specific": {
"cwe_ids": [
"CWE-116",
"CWE-89"
],
"github_reviewed": true,
"github_reviewed_at": "2026-08-28T22:53:12Z",
"nvd_published_at": null,
"severity": "MODERATE"
},
"details": "### Summary\n\nA SQL injection is possible when the connector escapes Buffer parameters client-side under a multi-byte client character set whose trail-byte range overlaps the ASCII backslash (0x5C): big5, gbk, sjis, cp932, and gb18030. Under these charsets, an attacker-controlled lead byte can absorb the escape byte the connector inserts, leaving the following quote unescaped so it terminates the string literal and injected SQL is parsed.\n\n### Details\n\nWhen binding a Buffer (binary) parameter, the connector escapes the value byte-by-byte, inserting a backslash (0x5C) before quote (0x27) and backslash bytes. This is correct under single-byte and UTF-8\u2013family charsets, but unsafe under client charsets whose multi-byte trail-byte range includes 0x5C.\n\nOn the server, the SQL lexer performs multi-byte character recognition (my_ismbchar) before it interprets escape sequences. If character_set_client is one of the affected charsets and the attacker controls a byte the lexer treats as a valid lead byte, the sequence \u003clead-byte\u003e\u003c0x5C\u003e is consumed as a single multi-byte character. The escaping backslash inserted by the connector is swallowed as that character\u0027s trail byte, so the following 0x27 is no longer escaped \u2014 it closes the string literal, and the remaining bytes are parsed as SQL.\n\nThis is the well-known multi-byte escaping bypass (the same class that historically affected addslashes / mysql_real_escape_string under GBK/Big5), here applied to the connector\u0027s client-side Buffer escaping path.\n\n### Am I affected?\n\nYou are affected if all of the following hold:\n\n\nYou use mariadb Connector/Node.js at a version below the patched releases listed below.\nThe connection\u0027s client character set is one of big5, gbk, sjis, cp932, or gb18030. This is not the default (the default is utf8mb4).\nUntrusted data can reach a Buffer-typed query parameter.\n\n\nApplications using utf8mb4 (or any charset whose trail-byte range does not include 0x5C) are not affected by this vector. Parameters bound through the binary/server-side prepared-statement path are also not affected, because those values are sent out-of-band and are never escaped into the SQL text.\n\n### Impact\n\nSQL injection. An attacker able to influence the contents of a Buffer parameter can break out of the intended string literal and inject arbitrary SQL, leading to unauthorized read or modification of data and, depending on the database account\u0027s privileges, further compromise.\n\n### Patches\n\nFixed in 3.2.4, 3.3.3, 3.4.6, and 3.5.3. Upgrade to the patched release on your branch:\n\n\n* 3.5.x \u2192 3.5.3\n* 3.4.x \u2192 3.4.6\n* 3.3.x \u2192 3.3.3\n* 3.2.x and earlier \u2192 3.2.4 (or any newer release)\n\n\n### Workarounds\n\nIf you cannot upgrade immediately:\n\nUse server-side prepared statements (execute) so parameters are bound via the binary protocol rather than escaped into the SQL text.\nAvoid passing untrusted data as Buffer parameters under the affected charsets.\n\n\nCredit\n\nReported by Yalguun Tumenkhuu ([@fg0x0](https://github.com/fg0x0/)).",
"id": "GHSA-g5xc-5w98-jfvm",
"modified": "2026-08-28T22:53:12Z",
"published": "2026-08-28T22:53:12Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/mariadb-corporation/mariadb-connector-nodejs/security/advisories/GHSA-g5xc-5w98-jfvm"
},
{
"type": "WEB",
"url": "https://github.com/mariadb-corporation/mariadb-connector-nodejs/commit/0148cadba48064d430902678bbc5b4b62dc1c04f"
},
{
"type": "PACKAGE",
"url": "https://github.com/mariadb-corporation/mariadb-connector-nodejs"
},
{
"type": "WEB",
"url": "https://jira.mariadb.org/browse/CONJS-350"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N",
"type": "CVSS_V3"
}
],
"summary": "MariaDB has possible SQL injection in Buffer parameter escaping under big5/gbk/sjis/cp932/gb18030 client charsets"
}
Mitigation MIT-4.3
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.
- For example, consider using the ESAPI Encoding control [REF-45] or a similar tool, library, or framework. These will help the programmer encode outputs in a manner less prone to error.
- Alternately, use built-in functions, but consider using wrappers in case those functions are discovered to have a vulnerability.
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.
- For example, stored procedures can enforce database query structure and reduce the likelihood of SQL injection.
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.
Mitigation
In some cases, input validation may be an important strategy when output encoding is not a complete solution. For example, you may be providing the same output that will be processed by multiple consumers that use different encodings or representations. In other cases, you may be required to allow user-supplied input to contain control information, such as limited HTML tags that support formatting in a wiki or bulletin board. When this type of requirement must be met, use an extremely strict allowlist to limit which control sequences can be used. Verify that the resulting syntactic structure is what you expect. Use your normal encoding methods for the remainder of the input.
Mitigation
Use input validation as a defense-in-depth measure to reduce the likelihood of output encoding errors (see CWE-20).
Mitigation
Fully specify which encodings are required by components that will be communicating with each other.
Mitigation
When exchanging data between components, ensure that both components are using the same character encoding. Ensure that the proper encoding is applied at each interface. Explicitly set the encoding you are using whenever the protocol allows you to do so.
CAPEC-104: Cross Zone Scripting
An attacker is able to cause a victim to load content into their web-browser that bypasses security zone controls and gain access to increased privileges to execute scripting code or other web objects such as unsigned ActiveX controls or applets. This is a privilege elevation attack targeted at zone-based web-browser security.
CAPEC-73: User-Controlled Filename
An attack of this type involves an adversary inserting malicious characters (such as a XSS redirection) into a filename, directly or indirectly that is then used by the target software to generate HTML text or other potentially executable content. Many websites rely on user-generated content and dynamically build resources like files, filenames, and URL links directly from user supplied data. In this attack pattern, the attacker uploads code that can execute in the client browser and/or redirect the client browser to a site that the attacker owns. All XSS attack payload variants can be used to pass and exploit these vulnerabilities.
CAPEC-81: Web Server Logs Tampering
Web Logs Tampering attacks involve an attacker injecting, deleting or otherwise tampering with the contents of web logs typically for the purposes of masking other malicious behavior. Additionally, writing malicious data to log files may target jobs, filters, reports, and other agents that process the logs in an asynchronous attack pattern. This pattern of attack is similar to "Log Injection-Tampering-Forging" except that in this case, the attack is targeting the logs of the web server and not the application.
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.