All vulnerabilities
CVE-2026-104817GHSA-4x7v-qx8f-g3p8

Misskey: Lack of rate limiting and size restrictions in RSS fetching API

misskey-dev misskey
Open in ThreatlineRecord JSON
CVSS
8.7High
ExploitationNo known exploitationNot in CISA KEV, which does not prove it is unexploitedCISA KEV
Exploit odds (EPSS)0.46%Chance of exploitation activity in the next 30 days, higher than 38% of CVEs. Scored 23 Oct 2026FIRST EPSS
Fixed in2026.7.0Fixed versionGitHub
Published13 Oct 2026Updated 13 Oct 2026CVE List

What fixes it

A fixed version on one release line is not the upgrade target for every line. Check your exact version and any vendor backports.

Description

Misskey is an open source, federated social media platform. From 12.112.1 until 2026.7.0, the unauthenticated fetch-rss API lacks rate limiting and response-size restrictions and performs synchronous XML parsing. An attacker can trigger unbounded outbound HTTP requests and synchronous parsing, exhausting instance resources, amplifying requests toward third-party servers, or probing network-reachable services even when federation is disabled. This issue is fixed in version 2026.7.0.

Text from CVE List

Affected versions 3

  • misskeyaffected: >= 12.0.0, <= 13.14.2CVE List
  • misskeyaffected: >= 2023.9.0-beta.1, < 2026.7.0CVE List
  • Misskey, n/a>= 12.112.1GitHub

References 3