CVE-2026-40911
WWBN AVideo YPTSocket WebSocket Broadcast Relay Leads to Unauthenticated Cross-User JavaScript Execution via Client-Side eval() Sinks
Description
WWBN AVideo is an open source video platform. In versions 29.0 and prior, the YPTSocket plugin's WebSocket server relays attacker-supplied JSON message bodies to every connected client without sanitizing the `msg` or `callback` fields. On the client side, `plugin/YPTSocket/script.js` contains two `eval()` sinks fed directly by those relayed fields (`json.msg.autoEvalCodeOnHTML` at line 568 and `json.callback` at line 95). Because tokens are minted for anonymous visitors and never revalidated beyond decryption, an unauthenticated attacker can broadcast arbitrary JavaScript that executes in the origin of every currently-connected user (including administrators), resulting in universal account takeover, session theft, and privileged action execution. Commit c08694bf6264eb4decceb78c711baee2609b4efd contains a fix.
INFO
Published Date :
April 21, 2026, 9:16 p.m.
Last Modified :
April 27, 2026, 3:12 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | CRITICAL | [email protected] |
Solution
- Update AVideo to a version after 29.0.
- Apply the fix from commit c08694bf6264eb4decceb78c711baee2609b4efd.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-40911.
| URL | Resource |
|---|---|
| https://github.com/WWBN/AVideo/commit/c08694bf6264eb4decceb78c711baee2609b4efd | Patch |
| https://github.com/WWBN/AVideo/security/advisories/GHSA-gph2-j4c9-vhhr | Exploit Vendor Advisory |
| https://github.com/WWBN/AVideo/security/advisories/GHSA-gph2-j4c9-vhhr | Exploit Vendor Advisory |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-40911 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-40911
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-40911 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-40911 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
Initial Analysis by [email protected]
Apr. 27, 2026
Action Type Old Value New Value Added CPE Configuration OR *cpe:2.3:a:wwbn:avideo:*:*:*:*:*:*:*:* versions up to (including) 29.0 Added Reference Type GitHub, Inc.: https://github.com/WWBN/AVideo/commit/c08694bf6264eb4decceb78c711baee2609b4efd Types: Patch Added Reference Type CISA-ADP: https://github.com/WWBN/AVideo/security/advisories/GHSA-gph2-j4c9-vhhr Types: Exploit, Vendor Advisory Added Reference Type GitHub, Inc.: https://github.com/WWBN/AVideo/security/advisories/GHSA-gph2-j4c9-vhhr Types: Exploit, Vendor Advisory -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Apr. 22, 2026
Action Type Old Value New Value Added Reference https://github.com/WWBN/AVideo/security/advisories/GHSA-gph2-j4c9-vhhr -
New CVE Received by [email protected]
Apr. 21, 2026
Action Type Old Value New Value Added Description WWBN AVideo is an open source video platform. In versions 29.0 and prior, the YPTSocket plugin's WebSocket server relays attacker-supplied JSON message bodies to every connected client without sanitizing the `msg` or `callback` fields. On the client side, `plugin/YPTSocket/script.js` contains two `eval()` sinks fed directly by those relayed fields (`json.msg.autoEvalCodeOnHTML` at line 568 and `json.callback` at line 95). Because tokens are minted for anonymous visitors and never revalidated beyond decryption, an unauthenticated attacker can broadcast arbitrary JavaScript that executes in the origin of every currently-connected user (including administrators), resulting in universal account takeover, session theft, and privileged action execution. Commit c08694bf6264eb4decceb78c711baee2609b4efd contains a fix. Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H Added CWE CWE-94 Added Reference https://github.com/WWBN/AVideo/commit/c08694bf6264eb4decceb78c711baee2609b4efd Added Reference https://github.com/WWBN/AVideo/security/advisories/GHSA-gph2-j4c9-vhhr