Improper Authorization in Mastodon - CVE-2026-33869
Published: April 23, 2026
Vulnerability identifier: #VU126997
CSH Severity: Medium
CVSS v4.0: 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/E:U/U:Green
CVE-ID: CVE-2026-33869
CWE-ID: CWE-285
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: Mastodon
Affected software:
Mastodon
Mastodon
Detailed vulnerability description
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.
How to mitigate CVE-2026-33869
Install security update from vendor's website.