CVE-2026-5132
Medium
Description
Mattermost versions 11.9.x <= 11.9.0, 11.8.x <= 11.8.4, 11.7.x <= 11.7.7, 10.11.x <= 10.11.22 fail to limit size of unpacked SDP messages compressed with zlib, which allows attacker to deny service or crash server via sending many SDP messages that unpack to large size.. Mattermost Advisory ID: MMSA-2026-00643
SeverityMedium
CVSS6.5
Exploit probability—
Product
Mattermost Server
PublishedSep 14, 2026
First seenSep 14, 2026
Weakness typeCWE-409CWE-409
How to fix
Update
- mattermost mattermost_server10.11.23, 11.7.8, 11.8.5, 11.9.1 or later
Vendor advisories
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| mattermost mattermost_server | 10.11.0 ≤ v < 10.11.23, 11.7.0 ≤ v < 11.7.8, 11.8.0 ≤ v < 11.8.5, 11.9.0 ≤ v < 11.9.1 | 10.11.23, 11.7.8, 11.8.5, 11.9.1 |
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