{"id":"CVE-2025-20086","aliases":["GHSA-5m7j-6gc4-ff5g","GO-2025-3392"],"title":"Mattermost fails to properly validate post props","summary":"Mattermost fails to properly validate post props","severity":"medium","cvss":6.5,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","vendor":"mattermost","product":"github.com/mattermost/mattermost/server/v8","ecosystem":"go","affected":["github.com/mattermost/mattermost/server/v8 >= 10.2.0, < 10.2.1","github.com/mattermost/mattermost/server/v8 >= 10.1.0, < 10.1.4","github.com/mattermost/mattermost/server/v8 >= 10.0.0, < 10.0.4","github.com/mattermost/mattermost/server/v8 >= 9.11.0, < 9.11.6","github.com/mattermost/mattermost/server/v8 < 8.0.0-20241127161322-25ff7a3779a5"],"patched":["github.com/mattermost/mattermost/server/v8 10.2.1","github.com/mattermost/mattermost/server/v8 10.1.4","github.com/mattermost/mattermost/server/v8 10.0.4","github.com/mattermost/mattermost/server/v8 9.11.6","github.com/mattermost/mattermost/server/v8 8.0.0-20241127161322-25ff7a3779a5"],"published":"2025-01-15","updated":"2026-09-10","sourceUpdated":"2026-09-10T03:50:21.861419050Z","source":"OSV","sourceUrl":"https://osv.dev/vulnerability/GHSA-5m7j-6gc4-ff5g","references":[{"url":"https://nvd.nist.gov/vuln/detail/CVE-2025-20086"},{"url":"https://github.com/mattermost/mattermost"},{"url":"https://mattermost.com/security-updates"},{"url":"https://pkg.go.dev/vuln/GO-2025-3392"}],"tags":["osv","go"],"epss":0.00428,"epssPercentile":0.36676,"ingestedAt":"2026-09-12T03:13:01.756Z","slug":"CVE-2025-20086","body":"## Overview\n\nMattermost 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.\n\n## Affected packages\n\n- `github.com/mattermost/mattermost/server/v8 >= 10.2.0, < 10.2.1`\n- `github.com/mattermost/mattermost/server/v8 >= 10.1.0, < 10.1.4`\n- `github.com/mattermost/mattermost/server/v8 >= 10.0.0, < 10.0.4`\n- `github.com/mattermost/mattermost/server/v8 >= 9.11.0, < 9.11.6`\n- `github.com/mattermost/mattermost/server/v8 < 8.0.0-20241127161322-25ff7a3779a5`\n\n## Remediation\n\nUpgrade to a patched release:\n\n- `github.com/mattermost/mattermost/server/v8 10.2.1`\n- `github.com/mattermost/mattermost/server/v8 10.1.4`\n- `github.com/mattermost/mattermost/server/v8 10.0.4`\n- `github.com/mattermost/mattermost/server/v8 9.11.6`\n- `github.com/mattermost/mattermost/server/v8 8.0.0-20241127161322-25ff7a3779a5`","depth":"sunlit","depthScore":36,"depthScoreParts":{"impact":35.8,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}