Vulnerability Description
WWBN AVideo is an open source video platform. In versions up to and including 26.0, the fix for CVE-2026-27568 (GHSA-rcqw-6466-3mv7) introduced a custom `ParsedownSafeWithLinks` class that sanitizes raw HTML `<a>` and `<img>` tags in comments, but explicitly disables Parsedown's `safeMode`. This creates a bypass: markdown link syntax `[text](javascript:alert(1))` is processed by Parsedown's `inlineLink()` method, which does not go through the custom `sanitizeATag()` sanitization (that only handles raw HTML tags). With `safeMode` disabled, Parsedown's built-in `javascript:` URI filtering (`sanitiseElement()`/`filterUnsafeUrlInAttribute()`) is also inactive. An attacker can inject stored XSS via comment markdown links. Commit 3ae02fa240939dbefc5949d64f05790fd25d728d contains a patch.
CVSS Score
MEDIUM
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Wwbn | Avideo | <= 26.0 |
Related Weaknesses (CWE)
References
- https://github.com/WWBN/AVideo/commit/3ae02fa240939dbefc5949d64f05790fd25d728dPatch
- https://github.com/WWBN/AVideo/security/advisories/GHSA-72h5-39r7-r26jExploitMitigationVendor Advisory
FAQ
What is CVE-2026-33500?
CVE-2026-33500 is a vulnerability with a CVSS score of 5.4 (MEDIUM). WWBN AVideo is an open source video platform. In versions up to and including 26.0, the fix for CVE-2026-27568 (GHSA-rcqw-6466-3mv7) introduced a custom `ParsedownSafeWithLinks` class that sanitizes r...
How severe is CVE-2026-33500?
CVE-2026-33500 has been rated MEDIUM with a CVSS base score of 5.4/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-33500?
Check the references section above for vendor advisories and patch information. Affected products include: Wwbn Avideo.