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TI-2026-25896 Aliases CVE-2026-33500GHSA-72h5-39r7-r26j

AVideo Vulnerable to Stored XSS via Markdown `javascript:` URI Bypasses ParsedownSafeWithLinks Sanitization

Priority MEDIUM 58CWE-79Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
Required
Attack complexity
Low
Impact type
Cross-site scripting
Confidentiality · integrity · availability
Low · Low · None
Fix status
No fix listed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub. Impact type from CWE-79.

Summary

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.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00226 13th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
WWBNAVideoup to 26.0—No fix listedCNA
—wwbn/avideo (Packagist)up to 26.0—No fix listedGHSA-72h5-39r7-r26j
  • AVideo VendorWWBN Affected up to 26.0 Fixed in — No fix listed CNA
  • wwbn/avideo (Packagist) Vendor— Affected up to 26.0 Fixed in — No fix listed GHSA-72h5-39r7-r26j

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:wwbn:avideo:*:*:*:*:*:*:*:*up to 26.0VulnerableWWBN
  • cpe:2.3:a:wwbn:avideo:*:*:*:*:*:*:*:* Versions up to 26.0 Vulnerable ·WWBN

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-33500
  2. 2026-10-03 Alias added: GHSA-72h5-39r7-r26j

References

  • TI-2026-29567 Code injection in WWBN AVideo CVSS 3.1CRITICAL 10.0
  • TI-2026-26095 AVideo Allows Unauthenticated Live Stream Control via Token Verification URL Override in control.json.php CVSS 3.1CRITICAL 9.4
  • TI-2026-25874 Improper access control in WWBN AVideo CVSS 3.1CRITICAL 10.0
  • TI-2026-25758 AVideo has an Unauthenticated SQL Injection via `doNotShowCats` Parameter (Backslash Escape Bypass) CVSS 3.1CRITICAL 9.8
  • TI-2024-20951 An issue in WWBN AVideo v.12.4 through v.14.2 allows a remote attacker to execute… CVSS 3.1CRITICAL 9.8
  • TI-2023-10706 OS injection vulnerability in World Wide Broadcast Network AVideo version before 12.4… CVSS 3.1CRITICAL 9.8
See all 189 →

Sources