# CVE-2026-3637: Mattermost fails to enforce create_post permission when editing posts

> CVE-2026-3637: Mattermost fails to enforce create_post permission when editing posts. CVSS 4.3 (CVSS 3.1).

Canonical: https://rewindex.com/cve/CVE-2026-3637
Last updated: 2026-10-14T20:10:00Z

- Published: 2026-05-18 06:53 UTC · Updated: 2026-10-14 20:10 UTC · Assigner: Mattermost
- CVSS: 4.3 (CVSS 3.1) · Severity: Medium · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
- EPSS: 0.15%, 4th percentile (scored 2026-10-25)
- CISA KEV: no
- CWE: CWE-862

## Description

Mattermost versions 11.5.x \<= 11.5.1, 10.11.x \<= 10.11.13, 11.4.x \<= 11.4.3 fail to check the create\_post channel permission during post edit operations which allows an authenticated attacker with revoked posting privileges to modify their existing posts via direct API requests to the post update and patch endpoints.. Mattermost Advisory ID: MMSA-2026-00627

## Affected vendors and products

- Mattermost: Mattermost

## Tracked companies

- [Mattermost](https://rewindex.com/company/mattermost.md)

## References

- [CVE record on cve.org](https://www.cve.org/CVERecord?id=CVE-2026-3637)
- [NVD entry](https://nvd.nist.gov/vuln/detail/CVE-2026-3637)
- [https://mattermost.com/security-updates](https://mattermost.com/security-updates)

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_Sources: CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (https://www.cve.org/) This product uses data from the NVD API but is not endorsed or certified by the NVD. (https://nvd.nist.gov/) Known Exploited Vulnerabilities catalog from CISA. (https://www.cisa.gov/known-exploited-vulnerabilities-catalog) EPSS scores from FIRST (Exploit Prediction Scoring System). (https://www.first.org/epss/)_


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Canonical: https://rewindex.com/cve/CVE-2026-3637 · Markdown: https://rewindex.com/cve/CVE-2026-3637.md · JSON: https://rewindex.com/api/v1/cves/CVE-2026-3637 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-10-26T03:10:07.915Z