CVE-2026-104817: high-severity vulnerability in misskey-dev misskey
Misskey: Lack of rate limiting and size restrictions in RSS fetching API
Published
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21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 8.7epss 0.5%
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.
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:L/SI:N/SA:L
Affected products
misskey-dev · misskeyRelated CVEs — misskey-dev misskey
In the same product, most dangerous first.
CVE-2021-39195HIGHServer-Side Request Forgery vulnerability in misskeyEPSS 1.1%CVE-2023-43793HIGHMisskey allows users to bypass authentication of Bull dashboardEPSS 0.8%CVE-2021-39169HIGHXSS vulnerability using dialogEPSS 0.7%CVE-2023-24812HIGHSQL injection of notes/search-by-tagEPSS 0.7%CVE-2024-25636HIGHLack of media type verification of Activity Streams objects allows impersonation and takeover of remote accountsEPSS 0.7%CVE-2026-104816HIGHMisskey: Cross-site scripting in RSS feed item linksEPSS 0.6%