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CVE-2026-9820

Mattermost schemes teams endpoint exposes private team invite IDs

Published: Jul 13, 2026Updated: Jul 13, 2026 Sources: CVE List NVDCWE-862
3.8LOW
NVD MITRE
EPSS Score
0.2%
Top 95.1%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available
Self-Check
OpenVAS

Description

Mattermost versions 11.7.x <= 11.7.2, 10.11.x <= 10.11.19 fail to sanitize team objects returned by the scheme teams endpoint, which allows a user with the User Manager role to obtain invite links for private teams and use them to join or share access to those teams via the scheme teams API endpoint.. Mattermost Advisory ID: MMSA-2026-00671

No summary for this CVE yet.

CVSS Vector Breakdown

AV:NAC:LPR:HUI:NS:UC:LI:LA:N
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:HPrivileges Required
High
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:LConfidentiality
Low
I:LIntegrity
Low
A:NAvailability
None
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Weaknesses

CWE-862

Affected Products

Mattermost
commercial·US
mattermost serverOn-premWeb App
Communications / messaging-chat
MattermostOn-premWeb App
Communications / messaging-chat

Exploitability

Official Patch Available
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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

2 techniques
Initial Access
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References

https://mattermost.com/security-updates
mattermost.com

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