CVE-2026-4635
MEDIUM EPSS 6.9%
Published May 22, 20261mo ago · Modified Jun 17, 20262w ago
5.3 CVSS 3.1
Published May 22, 2026 1mo ago
Last Modified Jun 17, 2026 2w ago
Description
Mattermost versions 11.6.x <= 11.6.0, 11.5.x <= 11.5.3, 11.4.x <= 11.4.4, 10.11.x <= 10.11.14 fail to archive the channel before removing persistent notifications which allows authenticated user to crash the server via timing the creation of persistent notification message between the server deleting existing persistent notifications and archiving the channel.. Mattermost Advisory ID: MMSA-2026-00637
CVSS Details
Base Score
Exploitability
Impact
Vector string
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H Attack Vector Network
Attack Complexity High
Privileges Required Low
User Interaction None
Scope Unchanged
Confidentiality None
Integrity None
Availability High
Threat Intelligence
EPSS Exploit Probability
6.9% percentile
Exploit & Patch Status
No Known Exploit
No Patch Available
Weaknesses 1
CWE-362
Affected Products 4
| Vendor | Product | Version | Range |
|---|---|---|---|
| mattermost | mattermost_server | * | ≥10.11.0 – <10.11.15 |
| mattermost | mattermost_server | * | ≥11.4.0 – <11.4.5 |
| mattermost | mattermost_server | * | ≥11.5.0 – <11.5.4 |
| mattermost | mattermost_server | * | ≥11.6.0 – <11.6.1 |
References 1
- mattermost.com https://mattermost.com/security-updates
Remediation
No remediation data recorded yet
Check vendor advisories and the NVD entry for patch availability.