Insufficient Input Validation on Post Props
Mattermost versions 10.2.x <= 10.2.0, 9.11.x <= 9.11.5, 10.0.x <= 10.0.3, 10.1.x <= 10.1.3 fail to properly validate post props which allows a malicious authenticated user to cause a crash via a malicious post.
02 / AFFECTED SOFTWARE
Affected packages
45 explicit affected versions
03 / CONNECTIONS
Connected vulnerabilities
04 / EVIDENCE
Source records
Mattermost versions 10.2.x <= 10.2.0, 9.11.x <= 9.11.5, 10.0.x <= 10.0.3, 10.1.x <= 10.1.3 fail to properly validate post props which allows a malicious authenticated user to cause a crash via a malicious post.
Mattermost versions 10.2.x <= 10.2.0, 9.11.x <= 9.11.5, 10.0.x <= 10.0.3, 10.1.x <= 10.1.3 fail to properly validate post props which allows a malicious authenticated user to cause a crash via a malicious post.
Mattermost fails to properly validate post props in github.com/mattermost/mattermost-server
05 / REFERENCES
Further evidence
- https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/20xxx/CVE-2025-20086.json
- https://mattermost.com/security-updates
- https://nvd.nist.gov/vuln/detail/CVE-2025-20086
- https://github.com/mattermost/mattermost
- https://pkg.go.dev/vuln/GO-2025-3392
- https://github.com/advisories/GHSA-5m7j-6gc4-ff5g