CVEvulnerability

CVE-2026-23961

5.3 MEDIUM Published 2026-01-22 Modified 2026-06-17 Official page ↗
Status
Analyzed
Published
2026-01-22
Last modified
2026-06-17
Assigner
[email protected]
CVSS 3.1 ([email protected])
5.3 MEDIUM — CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
Weaknesses
CWE-863

Description

Mastodon is a free, open-source social network server based on ActivityPub. Mastodon allows server administrators to suspend remote users to prevent interactions. However, some logic errors allow already-known posts from such suspended users to appear in timelines if boosted. Furthermore, under certain circumstances, previously-unknown posts from suspended users can be processed. This issue allows old posts from suspended users to occasionally end up on timelines on all Mastodon versions. Additionally, on Mastodon versions from v4.5.0 to v4.5.4, v4.4.5 to v4.4.11, v4.3.13 to v4.3.17, and v4.2.26 to v4.2.29, remote suspended users can partially bypass the suspension to get new posts in. Mastodon versions v4.5.5, v4.4.12, v4.3.18 are patched.

Affected configurations

• joinmastodon mastodon (< 4.3.18) • joinmastodon mastodon (>= 4.4.0 < 4.4.12) • joinmastodon mastodon (>= 4.5.0 < 4.5.5)

Related

Weakness · CWE (1)

  • CWE-863 Incorrect Authorization weakness

References