CVE-2026-47746

Misskey is an open source, federated social media platform. Versions 12.37.0 and later, but prior to 2026.5.4, are vulnerable to timing attacks during JSON-LD signature validation and the compaction process. Because the JSON-LD parsing context is not shared between signature verification and subsequent processing, the application may trust information that should not be trusted, resulting in a time-of-check to time-of-use (TOCTOU) flaw. This allows an attacker to have fraudulent activities accepted as valid, leading to a loss of integrity. This issue has been fixed in version 2026.5.4.

CVSS

No CVSS.

References

Link	Resource
https://github.com/misskey-dev/misskey/releases/tag/2026.5.4
https://github.com/misskey-dev/misskey/security/advisories/GHSA-38jx-423m-g387

Configurations

No configuration.

History

23 Oct 2026, 21:10

Type	Values Removed	Values Added
Summary		(es) Misskey es una plataforma de redes sociales de código abierto y federada. Las versiones 12.37.0 y posteriores, pero anteriores a la 2026.5.4, son vulnerables a ataques de temporización durante la validación de firmas JSON-LD y el proceso de compactación. Debido a que el contexto de análisis JSON-LD no se comparte entre la verificación de la firma y el procesamiento posterior, la aplicación puede confiar en información que no debería ser de confianza, lo que resulta en una falla de tiempo de verificación a tiempo de uso (TOCTOU). Esto permite a un atacante que actividades fraudulentas sean aceptadas como válidas, lo que lleva a una pérdida de integridad. Este problema ha sido solucionado en la versión 2026.5.4.

Information

Published : 2026-08-03 22:16

Updated : 2026-10-23 21:10

NVD link : CVE-2026-47746

Mitre link : CVE-2026-47746

CVE.ORG link : CVE-2026-47746

JSON object : View

Products Affected

No product.

CWE

CWE-367

Time-of-check Time-of-use (TOCTOU) Race Condition

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