WWBN AVideo up to 29.0 JSON Message script.js eval msg/callback code injection

CVSS Meta Temp Score
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CTI Interest Score
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8.5$0-$5k0.00

Summaryinfo

A vulnerability labeled as critical has been found in WWBN AVideo up to 29.0. This vulnerability affects the function eval of the file plugin/YPTSocket/script.js of the component JSON Message Handler. Such manipulation of the argument msg/callback leads to code injection. This vulnerability is uniquely identified as CVE-2026-40911. The attack can be launched remotely. No exploit exists. Applying a patch is advised to resolve this issue.

Detailsinfo

A vulnerability was found in WWBN AVideo up to 29.0 and classified as critical. Affected by this issue is the function eval of the file plugin/YPTSocket/script.js of the component JSON Message Handler. The manipulation of the argument msg/callback with an unknown input leads to a code injection vulnerability. Using CWE to declare the problem leads to CWE-94. The product constructs all or part of a code segment using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the syntax or behavior of the intended code segment. Impacted is confidentiality, integrity, and availability. CVE summarizes:

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.

The advisory is shared for download at github.com. This vulnerability is handled as CVE-2026-40911 since 04/15/2026. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. There are known technical details, but no exploit is available. The MITRE ATT&CK project declares the attack technique as T1059.

Applying the patch c08694bf6264eb4decceb78c711baee2609b4efd is able to eliminate this problem.

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Productinfo

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.6
VulDB Meta Temp Score: 8.5

VulDB Base Score: 7.3
VulDB Temp Score: 7.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 10.0
CNA Vector (GitHub_M): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Code injection
CWE: CWE-94 / CWE-74 / CWE-707
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔒

Patch: c08694bf6264eb4decceb78c711baee2609b4efd

Timelineinfo

04/15/2026 CVE reserved
04/21/2026 +6 days Advisory disclosed
04/21/2026 +0 days VulDB entry created
04/21/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-40911 (🔒)
GCVE (CVE): GCVE-0-2026-40911
GCVE (VulDB): GCVE-100-358592

Entryinfo

Created: 04/21/2026 22:37
Changes: 04/21/2026 22:37 (67)
Complete: 🔍
Cache ID: 216::103

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