Mastodon is a free, open-source social network server based on ActivityPub. In versions on the 4.5.x branch prior to 4.5.8 and on the 4.4.x branch prior to 4.4.15, an attacker that knows of a quote before it has reached a server can prevent it from being correctly processed on that server. The vulnerability has been patched in Mastodon 4.5.8 and 4.4.15. Mastodon 4.3 and earlier are not affected because they do not support quotes.
History

Sat, 28 Mar 2026 03:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Fri, 27 Mar 2026 20:15:00 +0000

Type Values Removed Values Added
Description Mastodon is a free, open-source social network server based on ActivityPub. In versions on the 4.5.x branch prior to 4.5.8 and on the 4.4.x branch prior to 4.4.15, an attacker that knows of a quote before it has reached a server can prevent it from being correctly processed on that server. The vulnerability has been patched in Mastodon 4.5.8 and 4.4.15. Mastodon 4.3 and earlier are not affected because they do not support quotes.
Title Mastodon has a denial of service for quote authorization
Weaknesses CWE-863
References
Metrics cvssV3_1

{'score': 4.8, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:L'}


cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-03-27T20:29:18.521Z

Reserved: 2026-03-24T15:10:05.678Z

Link: CVE-2026-33869

cve-icon Vulnrichment

Updated: 2026-03-27T20:29:14.109Z

cve-icon NVD

Status : Received

Published: 2026-03-27T20:16:34.500

Modified: 2026-03-27T20:16:34.500

Link: CVE-2026-33869

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

No data.