Medium severity · published Mar 26, 2026
CVE-2026-3112
Arbitrary File Read via Advanced Logging Support Packet
4.9
CVSS
0.4%
EPSS
No
On KEV
Description
Mattermost versions 11.4.x <= 11.4.0, 11.3.x <= 11.3.1, 11.2.x <= 11.2.3, 10.11.x <= 10.11.11 fail to validate Advanced Logging file target paths which allows system administrators to read arbitrary host files via malicious AdvancedLoggingJSON configuration in support packet generation. Mattermost Advisory ID: MMSA-2025-00562
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N
Attack vector
Network
Complexity
Low
Privileges
High
User interaction
None
Confidentiality
High
Integrity
None
Availability
None
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
11.4.0 through 11.4.0; 11.3.0 through 11.3.1; 11.2.0 through 11.2.3; 10.11.0 through 10.11.11 · source: vendor
MS
Mattermost Server · Mattermost
10.11.0 before 10.11.12; 11.2.0 before 11.2.4; 11.3.0 before 11.3.2; 11.4.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-3112
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-3112
Vendor Advisory
https://mattermost.com/security-updates
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