Medium severity · published Mar 16, 2026
CVE-2026-2461
Missing authorization check allows unauthorized modification of other users' comments on a board
4.3
CVSS
0.2%
EPSS
No
On KEV
Description
Mattermost Plugins versions <=11.3 11.0.3 11.2.2 10.10.11.0 fail to implement authorisation checks on comment block modifications, which allows an authorised attacker with editor permission to modify comments created by other board members. Mattermost Advisory ID: MMSA-2025-00559
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 6% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MA
Mattermost · Mattermost
through 11.0.3; through 11.2.2; through 10.10.11 · source: vendor
MS
Mattermost Server · Mattermost
before 10.11.11; 11.0.0 through 11.0.3; 11.1.0 before 11.2.3; 11.3.0 before 11.3.1 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-2461
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-2461
Vendor Advisory
https://mattermost.com/security-updates
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