CVE-2025-55073MS Teams plugin OAuth allows editing arbitrary posts
- 5.4MediumCVSS base score
- 0.20%Exploitation in 30 daysEPSS · top 91% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
Mattermost versions 10.11.x <= 10.11.3, 10.5.x <= 10.5.11, 10.12.x <= 10.12.0 fail to validate the relationship between the post being updated and the MSTeams plugin OAuth flow which allows an attacker to edit arbitrary posts via a crafted MSTeams plugin OAuth redirect URL.
Timeline
ID reserved
By Mattermost
- 30 days later
· 30 days later
Published
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| MattermostCNA (assigner) | 3.1 | Medium5.4 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L |
| NVDNVD · Analyzed | 3.1 | Medium5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N |
- EPSS (exploitation in 30 days)
- 0.20% · top 91% of all CVEs (14 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 5.4.
Affected products
- affected 10.11.0 – ≤ 10.11.3
- affected 10.5.0 – ≤ 10.5.11
- affected 10.12.0 – ≤ 10.12.0
- unaffected 11.0.0
- unaffected 10.11.4
- unaffected 10.5.12
- unaffected 10.12.1
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- Gogithub.com/mattermost/mattermost-serverGHSA-ff85-qw3h-g9vp (opens in a new tab)
- Gogithub.com/mattermost/mattermost/server/v8GHSA-ff85-qw3h-g9vp (opens in a new tab)
What to do
Solution: Update Mattermost to versions 11.0.0, 10.11.4, 10.5.12, 10.12.1 or higher.
References
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2025-186555 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-ff85-qw3h-g9vp (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2025-55073)Record last updated .