CVEvulnerability

CVE-2026-25540

6.5 MEDIUM Published 2026-02-04 Modified 2026-06-17 Official page ↗
Status
Analyzed
Published
2026-02-04
Last modified
2026-06-17
Assigner
[email protected]
CVSS 3.1 ([email protected])
6.5 MEDIUM — CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L
Weaknesses
CWE-524

Description

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.

Affected configurations

• joinmastodon mastodon (< 4.3.19) • joinmastodon mastodon (>= 4.4.0 < 4.4.13) • joinmastodon mastodon (>= 4.5.0 < 4.5.6)

Related

Weakness · CWE (1)

  • CWE-524 Use of Cache Containing Sensitive Information weakness

References