CVE-2026-5132 — Unbounded zlib decompression in Calls SDP WebSocket messages
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 atta…
Published: 2026-09-14 · CVSS: 6.5 · CVSS 3.1
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
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7