6.5mediumMedium

CVE-2026-5132

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

What the metrics mean

  • It is reachable over a network, without needing local access.
  • For an attacker who can reach it, no special conditions are needed to exploit it.
  • To exploit it, an ordinary user account is needed.
  • Beyond that, no action by a user is required.

Scoring

CVSS
6.5 (v3.1)
Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Weakness
CWE-409
Assigned by
responsibledisclosure@mattermost.com

Dates

Published
2026-09-14
Last modified
2026-09-14
Sources
NVD

References