CVE-2026-93849 (GCVE-0-2026-93849)
Vulnerability from cvelistv5
Published
2026-10-26 14:25
Modified
2026-10-26 16:46
Severity ?
6.5 (Medium) - CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
CWE
  • CWE-789 - Memory Allocation with Excessive Size Value
Summary
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
References
Impacted products
Vendor Product Version
Mattermost Mattermost Version: 11.9.0   ≤ 11.9.1
Version: 11.8.0   ≤ 11.8.5
Version: 11.7.0   ≤ 11.7.10
Version: 11.10.0   ≤ 11.10.1
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