Medium severity · published Aug 21, 2025
CVE-2025-8402
Nil pointer dereference in bulk import crashes server
4.9
CVSS
0.3%
EPSS
No
On KEV
Description
Mattermost versions 10.8.x <= 10.8.3, 10.5.x <= 10.5.8, 9.11.x <= 9.11.17, 10.10.x <= 10.10.0, 10.9.x <= 10.9.3 fail to validate import data which allows a system admin to crash the server via the bulk import feature.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
High
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 25% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MA
Mattermost · Mattermost
10.8.0 through 10.8.3; 10.5.0 through 10.5.8; 9.11.0 through 9.11.17; 10.10.0; 10.9.0 through 10.9.3 · source: vendor
MS
Mattermost Server · Mattermost
9.11.0 before 9.11.18; 10.5.0 before 10.5.9; 10.8.0 before 10.8.4; 10.9.0 before 10.9.4; 10.10.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-8402
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-8402
Vendor Advisory
https://mattermost.com/security-updates
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