CVE-2025-35965DoS in Mattermost Playbooks via Excessive Task Actions
- 6.5MediumCVSS base score
- 0.40%Exploitation in 30 daysEPSS · top 65% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
Mattermost versions 10.4.x <= 10.4.2, 10.5.x <= 10.5.0, 9.11.x <= 9.11.10 fail to validate the uniqueness and quantity of task actions within the UpdateRunTaskActions GraphQL operation, which allows an attacker to create task items containing an excessive number of actions triggered by specific posts, overloading the server and leading to a denial-of-service (DoS) condition.
Timeline
ID reserved
By Mattermost
- 2 days later
· 2 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 | Medium6.5 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |
| NVDNVD · Analyzed | 3.1 | High7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
- EPSS (exploitation in 30 days)
- 0.40% · top 65% 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 6.5.
Affected products
- affected 10.4.0 – ≤ 10.4.2
- affected 10.5.0
- affected 9.11.0 – ≤ 9.11.10
- unaffected 10.6.0
- unaffected 10.4.3
- unaffected 10.5.1
- unaffected 9.11.11
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- Gogithub.com/mattermost/mattermost-plugin-playbooksGHSA-689c-xq7x-xjwf (opens in a new tab)
- Gogithub.com/mattermost/mattermost/server/v8GHSA-689c-xq7x-xjwf (opens in a new tab)
What to do
Solution: Update Mattermost to versions 10.6.0, 10.4.3, 10.5.1, 9.11.11 or higher. Alternatively, update the Mattermost Playbooks plugin to version 2.1.1 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-2025-12105 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-689c-xq7x-xjwf (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-2025-35965)Record last updated .