Mattermost up to 10.11.21/11.7.6/11.8.3 Boards REST API privileges management

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.1$0-$5k0.41

Summaryinfo

A vulnerability categorized as critical has been discovered in Mattermost up to 10.11.21/11.7.6/11.8.3. This affects an unknown part of the component Boards REST API. Executing a manipulation can lead to privileges management. The identification of this vulnerability is CVE-2026-10527. The attack may be launched remotely. There is no exploit available.

Detailsinfo

A vulnerability classified as critical was found in Mattermost up to 10.11.21/11.7.6/11.8.3. This vulnerability affects an unknown functionality of the component Boards REST API. The manipulation with an unknown input leads to a privileges management vulnerability. The CWE definition for the vulnerability is CWE-269. The product does not properly assign, modify, track, or check privileges for an actor, creating an unintended sphere of control for that actor. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

Mattermost versions 11.7.x <= 11.7.6, 10.11.x <= 10.11.21, 11.8.x <= 11.8.3 fails to reconcile SchemeAdmin flags with a user's current role which allows a user demoted to System Guest to retain Board Admin privileges and perform admin-only operations via the Boards REST API or UI.. Mattermost Advisory ID: MMSA-2026-00691

The advisory is available at mattermost.com. This vulnerability was named CVE-2026-10527 since 06/01/2026. The exploitation appears to be easy. The attack can be initiated remotely. The technical details are unknown and an exploit is not available. This vulnerability is assigned to T1068 by the MITRE ATT&CK project.

Upgrading to version 10.11.22, 11.7.7, 11.8.4 or 11.9.0 eliminates this vulnerability.

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Productinfo

Type

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.3
VulDB Meta Temp Score: 6.1

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 6.3
CNA Vector (Mattermost): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Privileges management
CWE: CWE-269 / CWE-266
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Mattermost 10.11.22/11.7.7/11.8.4/11.9.0

Timelineinfo

06/01/2026 CVE reserved
08/17/2026 +77 days Advisory disclosed
08/17/2026 +0 days VulDB entry created
08/17/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: mattermost.com
Status: Confirmed

CVE: CVE-2026-10527 (🔒)
GCVE (CVE): GCVE-0-2026-10527
GCVE (VulDB): GCVE-100-391294

Entryinfo

Created: 08/17/2026 17:33
Changes: 08/17/2026 17:33 (63)
Complete: 🔍
Cache ID: 216::103

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