Vulnerability · Published Aug 3, 2026 · Assigned by GitHub_M
CVE-2026-46713Misskey: JSON-LD signature validation + compaction may lead to improper activity handling
Critical 9.2
In plain English
A critical-severity security flaw in misskey from misskey-dev. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 21% of all known vulnerabilities).
Severity (CVSS 4.0)9.2Critical
Exploit odds (30 days)0.3%top 79.4% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official 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.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| misskey-dev | misskey | >= 12.37.0, < 2026.5.4 |
Weakness: CWE-347 · Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:H/VA:N/SC:N/SI:H/SA:N
References
- https://github.com/misskey-dev/misskey/security/advisories/GHSA-w8x2-gpq6-jxvf x_refsource_CONFIRM
- https://github.com/misskey-dev/misskey/releases/tag/2026.5.4 x_refsource_MISC