Medium severity · published Jul 28, 2026
CVE-2026-7521
SAML certificate deletion allows path traversal to delete arbitrary files outside the config directory
5.5
CVSS
0.4%
EPSS
No
On KEV
Description
Mattermost versions 11.8.x <= 11.8.0, 11.7.x <= 11.7.3, 11.6.x <= 11.6.5, 10.11.x <= 10.11.20 fail to verify file deletion path which allows an admin with SAML system-console write permissions to delete arbitrary files outside the config directory from the server via the remove file endpoint.. Mattermost Advisory ID: MMSA-2026-00666
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:L/A:H
Attack vector
Network
Complexity
Low
Privileges
High
User interaction
None
Confidentiality
None
Integrity
Low
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 38% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MA
Mattermost · Mattermost
11.8.0 through 11.8.0; 11.7.0 through 11.7.3; 11.6.0 through 11.6.5; 10.11.0 through 10.11.20 · source: vendor
MS
Mattermost Server · Mattermost
10.11.0 before 10.11.21; 11.6.0 before 11.6.6; 11.7.0 before 11.7.4; 11.8.0 before 11.8.1 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-7521
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-7521
Vendor Advisory
https://mattermost.com/security-updates
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