Mattermost up to 10.5.10/10.11.2 Guest User Permission ids authorization

CVSS Meta Temp Score
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CTI Interest Score
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4.2$0-$5k0.00

Summaryinfo

A vulnerability labeled as problematic has been found in Mattermost up to 10.5.10/10.11.2. This issue affects some unknown processing of the file /api/v4/teams/{team_id}/channels/ids of the component Guest User Permission Handler. Such manipulation leads to authorization. This vulnerability is uniquely identified as CVE-2025-41443. The attack can be launched remotely. No exploit exists. The affected component should be upgraded.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in Mattermost up to 10.5.10/10.11.2. Affected by this issue is an unknown part of the file /api/v4/teams/{team_id}/channels/ids of the component Guest User Permission Handler. The manipulation with an unknown input leads to a authorization vulnerability. Using CWE to declare the problem leads to CWE-862. The product does not perform an authorization check when an actor attempts to access a resource or perform an action. Impacted is confidentiality. CVE summarizes:

Mattermost versions 10.5.x <= 10.5.12, 10.11.x <= 10.11.2 fail to properly validate guest user permissions when accessing channel information which allows guest users to discover active public channels and their metadata via the `/api/v4/teams/{team_id}/channels/ids` endpoint

The weakness was disclosed by lordwillmore. The advisory is shared for download at mattermost.com. This vulnerability is handled as CVE-2025-41443 since 09/16/2025. The exploitation is known to be easy. The attack may be launched remotely. There are known technical details, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 271200 (Mattermost Server 10.5.x < 10.5.11 / 10.11.x < 10.11.3 / 10.12.0 Multiple Vulnerabilities (MMSA-2025-00497, MMSA-2025-00496, MMSA-2025-00516)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 10.5.11, 10.11.3 or 10.12.0 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (271200) and EUVD (EUVD-2025-34731). Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.3
VulDB Meta Temp Score: 4.2

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 4.3
CNA Vector (Mattermost): 🔒

CVSSv2info

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

Exploitinginfo

Class: Authorization
CWE: CWE-862 / CWE-863 / CWE-285
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 271200
Nessus Name: Mattermost Server 10.5.x < 10.5.11 / 10.11.x < 10.11.3 / 10.12.0 Multiple Vulnerabilities (MMSA-2025-00497, MMSA-2025-00496, MMSA-2025-00516)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Mattermost 10.5.11/10.11.3/10.12.0

Timelineinfo

09/16/2025 CVE reserved
10/16/2025 +30 days Advisory disclosed
10/16/2025 +0 days VulDB entry created
10/29/2025 +13 days VulDB entry last update

Sourcesinfo

Advisory: mattermost.com
Researcher: lordwillmore
Status: Confirmed

CVE: CVE-2025-41443 (🔒)
GCVE (CVE): GCVE-0-2025-41443
GCVE (VulDB): GCVE-100-328772
EUVD: 🔒

Entryinfo

Created: 10/16/2025 10:33
Updated: 10/29/2025 11:08
Changes: 10/16/2025 10:33 (65), 10/23/2025 11:03 (2), 10/29/2025 10:23 (1), 10/29/2025 11:08 (1)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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