CVE-2026-47746
highpriority · track · 0EPSS 0.003 · 21 %ileEUEPSS · scored 2026-10-28
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
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.3–8.9
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (1)
Products and version ranges known to be affected.
also known as (2)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (6)
External citations — patches, advisories, analysis.
- https://github.com/misskey-dev/misskey/releases/tag/2026.5.4cnnvd
- https://github.com/misskey-dev/misskey/security/advisories/GHSA-38jx-423m-g387cnnvd
- https://github.com/misskey-dev/misskey/releases/tag/2026.5.4enisa_euvd
- https://github.com/misskey-dev/misskey/security/advisories/GHSA-38jx-423m-g387enisa_euvd
- https://github.com/misskey-dev/misskey/releases/tag/2026.5.4nvd
- https://github.com/misskey-dev/misskey/security/advisories/GHSA-38jx-423m-g387nvd
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