CVE-2026-9693
published 2026-08-17CVE-2026-9693: Mattermost versions 10.11.x <= 10.11.20, 11.7.x <= 11.7.5 Mattermost fails to remove thread membership records when a user is removed from or leaves a team…
PriorityP417low3.5CVSS 3.1
AVNACLPRLUIRSUCLINAN
EPSS
0.27%
18.3th percentile
Mattermost versions 10.11.x <= 10.11.20, 11.7.x <= 11.7.5 Mattermost fails to remove thread membership records when a user is removed from or leaves a team, which allows a previously removed user who is later re-invited to the team to view private channel thread root post content and metadata via the team threads API.. Mattermost Advisory ID: MMSA-2026-00682
Affected
4 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| mattermost | mattermost | 10.11.0 – 10.11.20 | — |
| mattermost | mattermost | 11.7.0 – 11.7.5 | — |
| mattermost | mattermost_server | >= 10.11.0 < 10.11.21 | 10.11.21 |
| mattermost | mattermost_server | >= 11.7.0 < 11.7.6 | 11.7.6 |
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VulDB
Mattermost up to 10.11.20/11.7.5 Team Threads API information disclosure (EUVD-2026-60542)
vuldb·2026-08-18·CVSS 3.5
CVE-2026-9693 [LOW] Mattermost up to 10.11.20/11.7.5 Team Threads API information disclosure (EUVD-2026-60542)
A vulnerability categorized as problematic has been discovered in Mattermost up to 10.11.20/11.7.5. This vulnerability affects unknown code of the component Team Threads API. Executing a manipulation can lead to information disclosure.
The identification of this vulnerability is CVE-2026-9693. The attack may be launched remotely. There is no exploit available.
It is advisable to upgrade the affected component.
GHSA
Mattermost versions 10.11.x <= 10.11.20, 11.7.x <= 11.7.5 Mattermost fails to remove thread membership records when a user is removed from or leaves a team, which allows a previously removed user who
ghsa_unreviewed·2026-08-18
CVE-2026-9693 [LOW] CWE-459 Mattermost versions 10.11.x <= 10.11.20, 11.7.x <= 11.7.5 Mattermost fails to remove thread membership records when a user is removed from or leaves a team, which allows a previously removed user who
Mattermost versions 10.11.x <= 10.11.20, 11.7.x <= 11.7.5 Mattermost fails to remove thread membership records when a user is removed from or leaves a team, which allows a previously removed user who is later re-invited to the team to view private channel thread root post content and metadata via the team threads API.. Mattermost Advisory ID: MMSA-2026-00682
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
2026-08-17
Published