High severity · published Oct 13, 2026
CVE-2026-103937
Misskey: Denial of service resulting from insufficient cleanup processing during file uploads
8.7
CVSS
0.5%
EPSS
No
On KEV
Description
Misskey is an open source, federated social media platform. From 13.0.0 until 2025.4.1 and from 2025.5.0 until 2026.7.0, cleanup processing may not execute during file uploads. Repeated uploads can exhaust storage or file descriptors and deny service regardless of whether federation is enabled. This issue is fixed in version 2026.7.0.
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 43% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MI
misskey · misskey-dev
>= 12.0.0, <= 13.14.2; >= 2023.9.0-beta.1, < 2025.4.1; >= 2025.5.0, < 2026.7.0 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-103937
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-103937
x_refsource_CONFIRM
https://github.com/misskey-dev/misskey/security/advisories/GHSA-m9xp-2fvm-pfmq
x_refsource_MISC
https://github.com/misskey-dev/misskey/pull/17750
x_refsource_MISC
https://github.com/misskey-dev/misskey/commit/3f28489fb856e6e07a16290f3ea1e1261572b527
x_refsource_MISC
https://github.com/misskey-dev/misskey/releases/tag/2026.7.0
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