CVE-2026-24458highCWE-770

CVE-2026-24458: high-severity vulnerability in Mattermost

DoS attack via login attempts with multi-megabyte passwords

Published

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21Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 7.5epss 0.3%
Mattermost versions 11.3.x <= 11.3.0, 11.2.x <= 11.2.2, 10.11.x <= 10.11.10 fail to properly handle very long passwords, which allows an attacker to overload the server CPU and memory via executing login attempts with multi-megabyte passwords. Mattermost Advisory ID: MMSA-2026-00587
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Affected products
Mattermost · Mattermost
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