CVSS 6.5 (medium) · published 2026-10-26
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
Affected products (NVD): mattermost mattermost_server
Fixed in (NVD): 11.7.11, 11.8.6, 11.9.2, 11.10.2
Weakness: CWE-789
Source: NVD CVE-2026-93849
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