High severity · published Oct 13, 2026
CVE-2026-104816
Misskey: Cross-site scripting in RSS feed item links
8.5
CVSS
0.6%
EPSS
No
On KEV
Description
Misskey is an open source, federated social media platform. From 12.0.0 until 2026.7.0, the RSS components display feed item links from configured feeds without verifying their URL schemes. Missing URL scheme verification allows an attacker who controls feed content to provide an unsafe-scheme link that causes script execution when a user clicks it in an RSS widget. This issue is fixed in version 2026.7.0.
Exploitation
Is it being used?
Exploit prediction (EPSS)0.6% · higher than 50% 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, < 2026.7.0 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-104816
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-104816
x_refsource_CONFIRM
https://github.com/misskey-dev/misskey/security/advisories/GHSA-p73x-6qrq-34jc
x_refsource_MISC
https://github.com/misskey-dev/misskey/pull/17831
x_refsource_MISC
https://github.com/misskey-dev/misskey/commit/8dd59a8c06da49b8f302d902d73d04397ee29366
x_refsource_MISC
https://github.com/misskey-dev/misskey/releases/tag/2026.7.0
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