CVE-2026-4053: low-severity vulnerability in Mattermost
post edit time limit is not enforced on some post update operations
Published
8Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 3.1epss 0.3%
exploitation probability
0.3%top 82% of all CVEs
observed exploitation
nono source reports it
Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13 fail to enforce the PostEditTimeLimit on non-message post fields which allows an authenticated user to modify post file attachments, props, and pin status after the edit window has expired via the post patch and update API endpoints.. Mattermost Advisory ID: MMSA-2026-00631
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:N
Affected products
Mattermost · MattermostRelated CVEs — Mattermost
In the same product, most dangerous first.
CVE-2025-25279CRITICALArbitrary file read in Mattermost Boards via import & export board archiveEPSS 24.2%CVE-2021-37859HIGHReflected XSS in OAuth FlowEPSS 3.3%CVE-2022-3257LOWServer-side Denial of Service while processing a specifically crafted GIF fileEPSS 1.3%CVE-2022-4044MEDIUMAuthenticated user could send multiple requests containing a large Auto Responder Message payload and can crash a Mattermost serverEPSS 1.1%CVE-2022-3147LOWServer-side Denial of Service while processing a specifically crafted JPEG fileEPSS 1.0%CVE-2022-1982MEDIUMA crafted SVG attachment can crash a Mattermost serverEPSS 0.9%
References
https://mattermost.com/security-updates