Low severity · published Oct 16, 2025
CVE-2025-54499
Insecure string comparison enables timing attacks
3.7
CVSS
0.3%
EPSS
No
On KEV
Description
Mattermost versions 10.5.x <= 10.5.10, 10.11.x <= 10.11.2 fail to use constant-time comparison for sensitive string comparisons which allows attackers to exploit timing oracles to perform byte-by-byte brute force attacks via response time analysis on Cloud API keys and OAuth client secrets
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Confidentiality
Low
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 19% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MA
Mattermost · Mattermost
10.5.0 through 10.5.10; 10.11.0 through 10.11.2 · source: vendor
MS
Mattermost Server · Mattermost
10.5.0 before 10.5.11; 10.11.0 before 10.11.3 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-54499
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-54499
Vendor Advisory
https://mattermost.com/security-updates
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