HTTP signature verification can be bypassed

Misskey is an open source, federated social media platform. All Misskey servers prior to 2026.3.1 contain a vulnerability that allows bypassing HTTP signature verification. Although this is a vulnerability related to federation, it affects all servers regardless of whether federation is enabled or disabled. This vulnerability is fixed in 2026.3.1.

Problem type

CWE-347: Improper Verification of Cryptographic Signature

Affected products

misskey-dev

misskey

< 2026.3.1 - AFFECTED

References

https://github.com/misskey-dev/misskey/security/advisories/GHSA-grwc-c762-gcvp

https://github.com/misskey-dev/misskey/security/advisories/GHSA-grwc-c762-gcvp

x_refsource_CONFIRM

JSON source

https://cveawg.mitre.org/api/cve/CVE-2026-28432

Click to expand

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    "dateUpdated": "2026-03-09T21:19:43.220Z",
    "dateReserved": "2026-02-27T15:54:05.137Z",
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