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Common Weakness Enumeration

CWE-80

Allowed

Improper Neutralization of Script-Related HTML Tags in a Web Page (Basic XSS)

Abstraction: Variant · Status: Incomplete

The product receives input from an upstream component, but it does not neutralize or incorrectly neutralizes special characters such as "<", ">", and "&" that could be interpreted as web-scripting elements when they are sent to a downstream component that processes web pages.

975 vulnerabilities reference this CWE, most recent first.

GHSA-GJ4P-RXXG-6JHM

Vulnerability from github – Published: 2026-08-18 15:31 – Updated: 2026-08-18 15:31
VLAI
Details

HTML Injection in the public subscription form in maalfer MailerUp before 1.1.3 allows unauthenticated remote attackers to have the application send a message carrying arbitrary HTML, to an attacker-chosen address and from the form owner's configured sending identity, via the first_name field of the subscription request, which is interpolated unescaped into the double opt-in verification email.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2026-75872"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-80"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-08-18T15:17:15Z",
    "severity": "MODERATE"
  },
  "details": "HTML Injection in the public subscription form in maalfer MailerUp before 1.1.3 allows unauthenticated remote attackers to have the application send a message carrying arbitrary HTML, to an attacker-chosen address and from the form owner\u0027s configured sending identity, via the first_name field of the subscription request, which is interpolated unescaped into the double opt-in verification email.",
  "id": "GHSA-gj4p-rxxg-6jhm",
  "modified": "2026-08-18T15:31:49Z",
  "published": "2026-08-18T15:31:49Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-75872"
    },
    {
      "type": "WEB",
      "url": "https://github.com/maalfer/mailerup/commit/da4aedc9621911df4ce0cc8f0b321dd6d10f40a5"
    },
    {
      "type": "WEB",
      "url": "https://github.com/maalfer/mailerup/releases/tag/v1.1.3"
    },
    {
      "type": "WEB",
      "url": "https://secur0.com/en/cna/cve-list/cve-2026-75872-html-injection-in-mailerup-double-optin-verification-email"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
      "type": "CVSS_V4"
    }
  ]
}

GHSA-GJMQ-X5X7-WC36

Vulnerability from github – Published: 2022-09-16 17:39 – Updated: 2022-09-16 17:39
VLAI
Summary
XWiki Platform vulnerable to Cross-site Scripting in the deleted attachments list
Details

Impact

It's possible to store a JavaScript which will be executed by anyone viewing the deleted attachments index with an attachment containing javascript in its name.

For example, attachment a file with name ><img src=1 onerror=alert(1)>.jpg will execute the alert.

Patches

This issue has been patched in XWiki 13.10.6 and 14.3.

Workarounds

It is possible to modify fix the vulnerability by editing the wiki page XWiki.DeletedAttachments with the object editor, open the JavaScriptExtension object and apply on the content the changes that can be found on the commit https://github.com/xwiki/xwiki-platform/commit/6705b0cd0289d1c90ed354bd4ecc1508c4b25745.

References

  • https://jira.xwiki.org/browse/XWIKI-19613

For more information

If you have any questions or comments about this advisory: * Open an issue in Jira XWiki.org * Email us at Security Mailing List

Show details on source website

{
  "affected": [
    {
      "package": {
        "ecosystem": "Maven",
        "name": "org.xwiki.platform:xwiki-platform-index-ui"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "2.2-milestone-1"
            },
            {
              "fixed": "13.10.6"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Maven",
        "name": "org.xwiki.platform:xwiki-platform-index-ui"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "14.0"
            },
            {
              "fixed": "14.3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2022-36096"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-79",
      "CWE-80"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2022-09-16T17:39:32Z",
    "nvd_published_at": "2022-09-08T21:15:00Z",
    "severity": "HIGH"
  },
  "details": "### Impact\n\nIt\u0027s possible to store a JavaScript which will be executed by anyone viewing the deleted attachments index with an attachment containing javascript in its name.\n\nFor example, attachment a file with name `\u003e\u003cimg src=1 onerror=alert(1)\u003e.jpg` will execute the alert.\n\n### Patches\n\nThis issue has been patched in XWiki 13.10.6 and 14.3.\n\n### Workarounds\n\nIt is possible to modify fix the vulnerability by editing the wiki page `XWiki.DeletedAttachments` with the object editor, open the `JavaScriptExtension` object and apply on the content the changes that can be found on the commit https://github.com/xwiki/xwiki-platform/commit/6705b0cd0289d1c90ed354bd4ecc1508c4b25745.\n\n### References\n\n* https://jira.xwiki.org/browse/XWIKI-19613\n\n### For more information\n\nIf you have any questions or comments about this advisory:\n* Open an issue in [Jira XWiki.org](https://jira.xwiki.org/)\n* Email us at [Security Mailing List](mailto:security@xwiki.org)\n",
  "id": "GHSA-gjmq-x5x7-wc36",
  "modified": "2022-09-16T17:39:32Z",
  "published": "2022-09-16T17:39:32Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/xwiki/xwiki-platform/security/advisories/GHSA-gjmq-x5x7-wc36"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2022-36096"
    },
    {
      "type": "WEB",
      "url": "https://github.com/xwiki/xwiki-platform/commit/6705b0cd0289d1c90ed354bd4ecc1508c4b25745"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/xwiki/xwiki-platform"
    },
    {
      "type": "WEB",
      "url": "https://jira.xwiki.org/browse/XWIKI-19613"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:L",
      "type": "CVSS_V3"
    }
  ],
  "summary": "XWiki Platform vulnerable to Cross-site Scripting in the deleted attachments list"
}

GHSA-GJW6-Q3RJ-VMV6

Vulnerability from github – Published: 2025-09-22 21:30 – Updated: 2026-04-01 18:36
VLAI
Details

Improper Neutralization of Script-Related HTML Tags in a Web Page (Basic XSS) vulnerability in CozyThemes Cozy Blocks allows Code Injection. This issue affects Cozy Blocks: from n/a through 2.1.29.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2025-59573"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-80"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2025-09-22T19:16:25Z",
    "severity": "MODERATE"
  },
  "details": "Improper Neutralization of Script-Related HTML Tags in a Web Page (Basic XSS) vulnerability in CozyThemes Cozy Blocks allows Code Injection. This issue affects Cozy Blocks: from n/a through 2.1.29.",
  "id": "GHSA-gjw6-q3rj-vmv6",
  "modified": "2026-04-01T18:36:19Z",
  "published": "2025-09-22T21:30:28Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-59573"
    },
    {
      "type": "WEB",
      "url": "https://patchstack.com/database/wordpress/plugin/cozy-addons/vulnerability/wordpress-cozy-blocks-plugin-2-1-29-content-injection-vulnerability?_s_id=cve"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-GJW6-QPFF-PF5X

Vulnerability from github – Published: 2026-06-25 15:32 – Updated: 2026-06-25 15:32
VLAI
Details

Content injected to PDF rendering contexts could, in many places, include HTML content including tags. If the src attribute of these images pointed to an URL, the PDF rendering engine would download the image from that place and display it, thereby leaking information about the rendering server and possibly creating an SSRF vector in the local network.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2026-57535"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-80"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-06-25T15:16:41Z",
    "severity": "LOW"
  },
  "details": "Content injected to PDF rendering contexts could, in many places, include HTML content including \u003cimg\u003e tags. If the src\n attribute of these images pointed to an URL, the PDF rendering engine \nwould download the image from that place and display it, thereby leaking\n information about the rendering server and possibly creating an SSRF \nvector in the local network.",
  "id": "GHSA-gjw6-qpff-pf5x",
  "modified": "2026-06-25T15:32:02Z",
  "published": "2026-06-25T15:32:02Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-57535"
    },
    {
      "type": "WEB",
      "url": "https://pretix.eu/about/en/blog/20260625-release-2026-5-2"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:L/VI:L/VA:L/SC:L/SI:L/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
      "type": "CVSS_V4"
    }
  ]
}

GHSA-GMGJ-54WW-GQ69

Vulnerability from github – Published: 2025-12-20 06:30 – Updated: 2025-12-20 06:30
VLAI
Details

The "Amazon affiliate lite Plugin" plugin for WordPress is vulnerable to Stored Cross-Site Scripting via admin settings in all versions up to, and including, 1.0.0 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with administrator-level permissions and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. This only affects multi-site installations and installations where unfiltered_html has been disabled.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2025-14735"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-80"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2025-12-20T04:16:08Z",
    "severity": "MODERATE"
  },
  "details": "The \"Amazon affiliate lite Plugin\" plugin for WordPress is vulnerable to Stored Cross-Site Scripting via admin settings in all versions up to, and including, 1.0.0 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with administrator-level permissions and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. This only affects multi-site installations and installations where unfiltered_html has been disabled.",
  "id": "GHSA-gmgj-54ww-gq69",
  "modified": "2025-12-20T06:30:12Z",
  "published": "2025-12-20T06:30:12Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-14735"
    },
    {
      "type": "WEB",
      "url": "https://plugins.trac.wordpress.org/browser/afiliados-de-amazon-lite/trunk/ADAL-core.php?rev=1952216#L105"
    },
    {
      "type": "WEB",
      "url": "https://plugins.trac.wordpress.org/browser/afiliados-de-amazon-lite/trunk/ADAL-core.php?rev=1952216#L236"
    },
    {
      "type": "WEB",
      "url": "https://www.wordfence.com/threat-intel/vulnerabilities/id/0c23cc3c-3c76-4ba8-8fa6-6ed0507a35c9?source=cve"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:L/I:L/A:N",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-GV2R-XMGW-W3FM

Vulnerability from github – Published: 2025-05-01 09:32 – Updated: 2026-04-08 18:33
VLAI
Details

The Team Members – Best WordPress Team Plugin with Team Slider, Team Showcase & Team Builder plugin for WordPress is vulnerable to Stored Cross-Site Scripting via Social Link icons in all versions up to, and including, 3.4.0 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with Contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2025-3521"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-80"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2025-05-01T07:15:58Z",
    "severity": "MODERATE"
  },
  "details": "The Team Members \u2013 Best WordPress Team Plugin with Team Slider, Team Showcase \u0026 Team Builder plugin for WordPress is vulnerable to Stored Cross-Site Scripting via Social Link icons in all versions up to, and including, 3.4.0 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with Contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.",
  "id": "GHSA-gv2r-xmgw-w3fm",
  "modified": "2026-04-08T18:33:52Z",
  "published": "2025-05-01T09:32:27Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-3521"
    },
    {
      "type": "WEB",
      "url": "https://plugins.trac.wordpress.org/changeset?sfp_email=\u0026sfph_mail=\u0026reponame=\u0026old=3286466%40wps-team\u0026new=3286466%40wps-team\u0026sfp_email=\u0026sfph_mail="
    },
    {
      "type": "WEB",
      "url": "https://wordpress.org/plugins/wps-team"
    },
    {
      "type": "WEB",
      "url": "https://www.wordfence.com/threat-intel/vulnerabilities/id/93b83e65-09d6-4ad5-85f3-d18a9a35f39d?source=cve"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-GWP7-78VH-MPMM

Vulnerability from github – Published: 2024-05-05 21:30 – Updated: 2025-11-04 18:30
VLAI
Details

An issue was discovered in includes/CommentFormatter/CommentParser.php in MediaWiki before 1.39.7, 1.40.x before 1.40.3, and 1.41.x before 1.41.1. XSS can occur because of mishandling of the 0x1b character, as demonstrated by Special:RecentChanges#%1b0000000.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2024-34507"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-80"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2024-05-05T19:15:07Z",
    "severity": "HIGH"
  },
  "details": "An issue was discovered in includes/CommentFormatter/CommentParser.php in MediaWiki before 1.39.7, 1.40.x before 1.40.3, and 1.41.x before 1.41.1. XSS can occur because of mishandling of the 0x1b character, as demonstrated by Special:RecentChanges#%1b0000000.",
  "id": "GHSA-gwp7-78vh-mpmm",
  "modified": "2025-11-04T18:30:55Z",
  "published": "2024-05-05T21:30:31Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2024-34507"
    },
    {
      "type": "WEB",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FU2FGUXXK6TMV6R52VRECLC6XCSQQISY"
    },
    {
      "type": "WEB",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/FU2FGUXXK6TMV6R52VRECLC6XCSQQISY"
    },
    {
      "type": "WEB",
      "url": "https://phabricator.wikimedia.org/T355538"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:N/A:N",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-H2FM-479P-V37R

Vulnerability from github – Published: 2025-10-30 12:31 – Updated: 2025-10-30 12:31
VLAI
Details

A Improper Neutralization of Script-Related HTML Tags in a Web Page (Basic XSS) vulnerability allows attackers to run arbitrary javascript via a reflected XSS issue in the search fields.This issue affects Container suse/manager/5.0/x86_64/server:latest: from ? before 5.0.28-150600.3.36.8; SUSE Manager Server LTS 4.3: from ? before 4.3.88-150400.3.113.5.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2025-53883"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-80"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2025-10-30T11:15:33Z",
    "severity": "CRITICAL"
  },
  "details": "A Improper Neutralization of Script-Related HTML Tags in a Web Page (Basic XSS) vulnerability allows attackers to run arbitrary javascript via a reflected XSS issue in the search fields.This issue affects Container suse/manager/5.0/x86_64/server:latest: from ? before 5.0.28-150600.3.36.8; SUSE Manager Server LTS 4.3: from ? before 4.3.88-150400.3.113.5.",
  "id": "GHSA-h2fm-479p-v37r",
  "modified": "2025-10-30T12:31:11Z",
  "published": "2025-10-30T12:31:11Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-53883"
    },
    {
      "type": "WEB",
      "url": "https://bugzilla.suse.com/show_bug.cgi?id=CVE-2025-53883"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:H/VI:H/VA:N/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
      "type": "CVSS_V4"
    }
  ]
}

GHSA-H45C-25X4-6QQ4

Vulnerability from github – Published: 2023-08-08 18:30 – Updated: 2024-09-27 21:31
VLAI
Details

Improper input validation in Zoom SDK’s before 5.14.10 may allow an unauthenticated user to enable a denial of service via network access.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2023-39217"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-20",
      "CWE-80"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2023-08-08T18:15:23Z",
    "severity": "HIGH"
  },
  "details": "Improper input validation in Zoom SDK\u2019s before 5.14.10 may allow an unauthenticated user to enable a denial of service via network access.",
  "id": "GHSA-h45c-25x4-6qq4",
  "modified": "2024-09-27T21:31:45Z",
  "published": "2023-08-08T18:30:37Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2023-39217"
    },
    {
      "type": "WEB",
      "url": "https://explore.zoom.us/en/trust/security/security-bulletin"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-H8FH-8C4J-6M47

Vulnerability from github – Published: 2025-09-17 06:30 – Updated: 2025-09-17 06:30
VLAI
Details

The Memberlite Shortcodes plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the plugins's 'row' shortcode in all versions up to, and including, 1.4 due to insufficient input sanitization and output escaping on user supplied attributes. This makes it possible for authenticated attackers, with contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2025-10125"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-80"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2025-09-17T04:15:53Z",
    "severity": "MODERATE"
  },
  "details": "The Memberlite Shortcodes plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the plugins\u0027s \u0027row\u0027 shortcode in all versions up to, and including, 1.4 due to insufficient input sanitization and output escaping on user supplied attributes. This makes it possible for authenticated attackers, with contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.",
  "id": "GHSA-h8fh-8c4j-6m47",
  "modified": "2025-09-17T06:30:22Z",
  "published": "2025-09-17T06:30:22Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-10125"
    },
    {
      "type": "WEB",
      "url": "https://plugins.trac.wordpress.org/browser/memberlite-shortcodes/tags/1.4/shortcodes/columns.php#L12"
    },
    {
      "type": "WEB",
      "url": "https://plugins.trac.wordpress.org/changeset?sfp_email=\u0026sfph_mail=\u0026reponame=\u0026old=3359252%40memberlite-shortcodes\u0026new=3359252%40memberlite-shortcodes\u0026sfp_email=\u0026sfph_mail="
    },
    {
      "type": "WEB",
      "url": "https://www.wordfence.com/threat-intel/vulnerabilities/id/ceb7316e-8b55-4e7a-9309-8a9e84f22c90?source=cve"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N",
      "type": "CVSS_V3"
    }
  ]
}

Mitigation
Implementation

Carefully check each input parameter against a rigorous positive specification (allowlist) defining the specific characters and format allowed. All input should be neutralized, 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. We often encounter 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.

Mitigation MIT-30.1
Implementation

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
Implementation

With Struts, write all data from form beans with the bean's filter attribute set to true.

Mitigation MIT-31
Implementation

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.

CAPEC-18: XSS Targeting Non-Script Elements

This attack is a form of Cross-Site Scripting (XSS) where malicious scripts are embedded in elements that are not expected to host scripts such as image tags (<img>), comments in XML documents (< !-CDATA->), etc. These tags may not be subject to the same input validation, output validation, and other content filtering and checking routines, so this can create an opportunity for an adversary to tunnel through the application's elements and launch a XSS attack through other elements. As with all remote attacks, it is important to differentiate the ability to launch an attack (such as probing an internal network for unpatched servers) and the ability of the remote adversary to collect and interpret the output of said attack.

CAPEC-193: PHP Remote File Inclusion

In this pattern the adversary is able to load and execute arbitrary code remotely available from the application. This is usually accomplished through an insecurely configured PHP runtime environment and an improperly sanitized "include" or "require" call, which the user can then control to point to any web-accessible file. This allows adversaries to hijack the targeted application and force it to execute their own instructions.

CAPEC-32: XSS Through HTTP Query Strings

An adversary embeds malicious script code in the parameters of an HTTP query string and convinces a victim to submit the HTTP request that contains the query string to a vulnerable web application. The web application then procedes to use the values parameters without properly validation them first and generates the HTML code that will be executed by the victim's browser.

CAPEC-86: XSS Through HTTP Headers

An adversary exploits web applications that generate web content, such as links in a HTML page, based on unvalidated or improperly validated data submitted by other actors. XSS in HTTP Headers attacks target the HTTP headers which are hidden from most users and may not be validated by web applications.