Mattermost up to 10.11.5/10.12.2/11.0.4 Channel Membership authorization

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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3.9$0-$5k0.00

Summaryinfo

A vulnerability was found in Mattermost up to 10.11.5/10.12.2/11.0.4. It has been rated as problematic. This affects an unknown function of the component Channel Membership Handler. This manipulation causes authorization. This vulnerability is registered as CVE-2025-13324. Remote exploitation of the attack is possible. No exploit is available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability classified as problematic was found in Mattermost up to 10.11.5/10.12.2/11.0.4. Affected by this vulnerability is an unknown function of the component Channel Membership Handler. The manipulation with an unknown input leads to a authorization vulnerability. The CWE definition for the vulnerability is CWE-863. The product performs an authorization check when an actor attempts to access a resource or perform an action, but it does not correctly perform the check. This allows attackers to bypass intended access restrictions. As an impact it is known to affect integrity. The summary by CVE is:

Mattermost versions 10.11.x <= 10.11.5, 11.0.x <= 11.0.4, 10.12.x <= 10.12.2 fail to invalidate remote cluster invite tokens when using the legacy (version 1) protocol or when the confirming party does not provide a refreshed token, which allows an attacker who has obtained an invite token to authenticate as the remote cluster and perform limited actions on shared channels even after the invitation has been legitimately confirmed.

The weakness was published by daw10. It is possible to read the advisory at mattermost.com. This vulnerability is known as CVE-2025-13324 since 11/17/2025. The exploitation appears to be easy. The attack can be launched remotely. The technical details are unknown and an exploit is not publicly available.

Upgrading to version 10.11.6, 10.12.3, 11.0.5 or 11.1.0 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2025-203920). Be aware that VulDB is the high quality 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: 4.0
VulDB Meta Temp Score: 3.9

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

CNA Base Score: 3.7
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-863 / CWE-285 / CWE-266
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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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Mattermost 10.11.6/10.12.3/11.0.5/11.1.0

Timelineinfo

11/17/2025 CVE reserved
12/17/2025 +30 days Advisory disclosed
12/17/2025 +0 days VulDB entry created
12/24/2025 +7 days VulDB entry last update

Sourcesinfo

Advisory: mattermost.com
Researcher: daw10
Status: Confirmed

CVE: CVE-2025-13324 (🔒)
GCVE (CVE): GCVE-0-2025-13324
GCVE (VulDB): GCVE-100-337015
EUVD: 🔒

Entryinfo

Created: 12/17/2025 21:23
Updated: 12/24/2025 13:19
Changes: 12/17/2025 21:23 (64), 12/20/2025 20:21 (1), 12/24/2025 13:19 (6)
Complete: 🔍
Cache ID: 216::103

Be aware that VulDB is the high quality source for vulnerability data.

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