Description
Mattermost versions 11.10.x <= 11.10.0, 11.9.x <= 11.9.1, 11.8.x <= 11.8.5, 11.7.x <= 11.7.10 fail to cap the number and size of mention keys stored in a user's notification properties, and to bound the quadratic multibyte-keyword matching performed for each post, which allows an authenticated user to degrade post-processing latency and consume excessive CPU on behalf of other members of any channel they share via storing an oversized notify_props.mention_keys list on their own profile.. Mattermost Advisory ID: MMSA-2026-00773
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
Mattermost Mattermost
Default version status: unaffected
11.10.0 to ≤ 11.10.0affected11.9.0 to ≤ 11.9.1affected11.8.0 to ≤ 11.8.5affected11.7.0 to ≤ 11.7.10affected11.11.0unaffected11.10.1unaffected11.9.2unaffected11.8.6unaffected11.7.11unaffected