6.5

CVE-2026-25540

Mastodon's signature-dependent ActivityPub collection responses cached under signature-independent keys (Web Cache Poisoning via `Rails.cache`)

Mastodon is a free, open-source social network server based on ActivityPub. Prior to versions 4.3.19, 4.4.13, 4.5.6, Mastodon is vulnerable to web cache poisoning via `Rails.cache. When AUTHORIZED_FETCH is enabled, the ActivityPub endpoints for pinned posts and featured hashtags have contents that depend on the account that signed the HTTP request. However, these contents are stored in an internal cache and reused with no regards to the signing actor. As a result, an empty response generated for a blocked user account may be served to requests from legitimate non-blocked actors, or conversely, content intended for non-blocked actors may be returned to blocked actors. This issue has been patched in versions 4.3.19, 4.4.13, 4.5.6.
Daten sind bereitgestellt durch National Vulnerability Database (NVD)
Joinmastodon ≫ Mastodon Version < 4.3.19
Joinmastodon ≫ Mastodon Version >= 4.4.0 < 4.4.13
Joinmastodon ≫ Mastodon Version >= 4.5.0 < 4.5.6
Zu dieser CVE wurde keine Warnung gefunden.
EPSS Metriken
Typ Quelle Score Percentile
EPSS FIRST.org 0.39% 0.309
CVSS Metriken
Quelle Base Score Exploit Score Impact Score Vector String
security-advisories@github.com 6.5 3.9 2.5
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L
CWE-524 Use of Cache Containing Sensitive Information

The code uses a cache that contains sensitive information, but the cache can be read by an actor outside of the intended control sphere.

https://github.com/mastodon/mastodon/security/advisories/GHSA-ccpr-m53r-mfwr
Vendor Advisory