CVE-2026-93849Published

Mattermost allows authenticated users to trigger excessive memory allocation via crafted msgpack binary WebSocket frames

Exact source revision recorded 26 Oct 2026 17:35:31 UTC. It does not establish the source's current position. Latest evidence.

Recorded JSON

cve-program · CVE-2026-93849

Published

Mattermost versions 11.9.x <= 11.9.1, 11.8.x <= 11.8.5, 11.7.x <= 11.7.10, 11.10.x <= 11.10.1 Mattermost fail to apply allocation limits to the byte-string decode paths in its WebSocket msgpack decoder, which allows an authenticated remote attacker to cause excessive server memory allocation via a crafted binary WebSocket frame declaring a Bin32 payload length of up to 4,294,967,295 bytes.. Mattermost Advisory ID: MMSA-2026-00768

Source published: 26 Oct 2026 14:25:26 UTC
Source modified: 26 Oct 2026 16:46:45 UTC
Observed here: 26 Oct 2026 17:35:31 UTC
Source terms: CVE Program Terms of Use

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: cve-program · CVE Program Terms of Use. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS 3.1 · 6.5 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H