Go/github.com/mattermost/mattermost/server/v8 CVE-2026-8823: low 3.8, EPSS 0.32%

Mattermost has an Incorrect Authorization issue

Action: Upgrade github.com/mattermost/mattermost/server/v8 to 8.0.0-20260518160100-9bd77d3fc4d2 or later.

go get github.com/mattermost/mattermost/server/v8@v8.0.0-20260518160100-9bd77d3fc4d2

Affected

Fixed versions

Sources

• osv: GHSA-xmfh-3ccg-c9fx#Go/github.com/mattermost/mattermost/server/v8
• https://nvd.nist.gov/vuln/detail/CVE-2026-8823
• https://github.com/mattermost/mattermost/pull/36487
• https://github.com/mattermost/mattermost/commit/7972fc53f5c0b0175879a9737308a87b42db1f0b
• https://github.com/mattermost/mattermost/commit/9bd77d3fc4d2af3f7f0259a205174e76a1a276e1
• https://github.com/mattermost/mattermost/commit/c9bf3609fb9a3e5c2de94c50742c9b91fd723e3d
• https://github.com/mattermost/mattermost/commit/d9a55e394cd5bc15edb49e9606bec8fec03ac4c6
• https://docs.mattermost.com/security-guide/security-updates
• https://github.com/mattermost/mattermost
• https://github.com/mattermost/mattermost/releases/tag/v10.11.18
• https://github.com/mattermost/mattermost/releases/tag/v11.7.1

CVE-2026-8823 · published 2026-06-22T18:34:16Z · modified 2026-10-01T20:56:22.201788989Z · JSON