Medium severity · published Apr 16, 2025
CVE-2025-27936
Webhook Secret Exposure via Timing attack in MSteams plugin
5.9
CVSS
0.3%
EPSS
No
On KEV
Description
Mattermost Plugin MSTeams versions <2.1.0 and Mattermost Server versions 10.5.x <=10.5.1 with the MS Teams plugin enabled fail to perform constant time comparison on a MSTeams plugin webhook secret which allows an attacker to retrieve the webhook secret of the MSTeams plugin via a timing attack during webhook secret comparison.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Confidentiality
High
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 28% 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 10.5.1 · source: vendor
MT
MS Teams · Mattermost
before 2.1.0 · source: NVD
MS
Mattermost Server · Mattermost
before 10.5.2 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-27936
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-27936
Vendor Advisory
https://mattermost.com/security-updates
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