Improper Authorization in Mastodon - CVE-2026-33869
Published: April 23, 2026
Vulnerability identifier: #VU126997
CSH Severity: Medium
CVSS v4: 6.3 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-33869
CWE-ID: CWE-285
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to prevent a quote from being correctly processed on the server.
The vulnerability exists due to improper authorization handling in quote authorization when processing a quote before it has reached a server. A remote attacker can know of a quote in advance to prevent a quote from being correctly processed on the server.
Affected software
Mastodon
How to mitigate CVE-2026-33869
Install security update from vendor's website.
Mastodon - addressed in versions 4.4.15, 4.5.8