Critical severity · published Aug 3, 2026
CVE-2026-46713
Misskey: JSON-LD signature validation + compaction may lead to improper activity handling
9.2
CVSS
0.3%
EPSS
No
On KEV
Description
Misskey is an open source, federated social media platform. Versions 12.37.0 and later, but prior to 2026.5.4, contain a vulnerability in the JSON-LD signature validation and compaction process that allows spoofed activities to be accepted as valid. This issue has been fixed in version 2026.5.4.
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 20% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MI
misskey · misskey-dev
>= 12.37.0, < 2026.5.4 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-46713
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-46713
github.com
https://github.com/misskey-dev/misskey/releases/tag/2026.5.4
github.com
https://github.com/misskey-dev/misskey/security/advisories/GHSA-w8x2-gpq6-jxvf
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