CVE-2026-9812

CVE CVE-2026-9812EUVD EUVD-2026-77374Published 2026-09-14T10:43:45.000ZLast changed 2026-09-14T11:19:44.000ZCVSS 6.5

What the advisory describes

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 validate that a property field belongs to the specified run before updating its value which allows an authenticated user with run property-management access to crash the Playbooks plugin via a REST request referencing a property field that belongs to a different run. Mattermost Advisory ID: MMSA-2026-00684

Source: EUVD (ENISA), in the words of the advisory.

Products the advisory names

These come from the advisory itself, not from any check we performed.

Mattermost — Mattermost 11.9.0 ≤11.9.0; 11.8.0 ≤11.8.4; 11.7.0 ≤11.7.7; 10.11.0 ≤10.11.22

The versions shown are the advisory's own. Patchlage compares no version numbers and derives no judgement from them — which version is installed is something a person has to look up.

Carried in the product catalogue

An estate covering these products can be recorded in Patchlage. An advisory about them appears in the next morning's situation report.

Mattermost — Mattermost

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