Mattermost up to 9.11.17/10.5.8/10.10.x Board File Download Endpoint authorization

CVSS Meta Temp Score
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Current Exploit Price (≈)
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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 9.11.17/10.5.8/10.10.x. The impacted element is an unknown function of the component Board File Download Endpoint. Executing a manipulation can lead to authorization. This vulnerability is registered as CVE-2025-9081. It is possible to launch the attack remotely. No exploit is available. The affected component should be upgraded.

Detailsinfo

A vulnerability classified as problematic was found in Mattermost up to 9.11.17/10.5.8/10.10.x. This vulnerability affects an unknown part of the component Board File Download Endpoint. The manipulation with an unknown input leads to a authorization vulnerability. The CWE definition for the vulnerability is CWE-639. The system's authorization functionality does not prevent one user from gaining access to another user's data or record by modifying the key value identifying the data. As an impact it is known to affect confidentiality. CVE summarizes:

Mattermost versions 10.5.x <= 10.5.8, 9.11.x <= 9.11.17 fail to properly validate access controls which allows any authenticated user to download sensitive files via board file download endpoint using UUID enumeration

The weakness was published by daw10. The advisory is available at mattermost.com. This vulnerability was named CVE-2025-9081 since 08/15/2025. The exploitation appears to be difficult. The attack can be initiated remotely. The technical details are unknown and an exploit is not available.

The vulnerability scanner Nessus provides a plugin with the ID 266221 (Mattermost Server 9.11.x < 9.11.18 / 10.5.x < 10.5.9 / 10.11.0 Authorization Bypass (MMSA-2025-00502)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 9.11.18, 10.5.9 or 10.11.0 eliminates this vulnerability.

The vulnerability is also documented in the databases at CNNVD (CNNVD-202509-3168), Tenable (266221) and EUVD (EUVD-2025-30247). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Type

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

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

VulDB Base Score: 3.1
VulDB Temp Score: 3.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 6.5
NVD Vector: 🔒

CNA Base Score: 3.1
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-639 / 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: 🔒

0-DayUnlockUnlockUnlockUnlock
TodayUnlockUnlockUnlockUnlock

Nessus ID: 266221
Nessus Name: Mattermost Server 9.11.x < 9.11.18 / 10.5.x < 10.5.9 / 10.11.0 Authorization Bypass (MMSA-2025-00502)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Mattermost 9.11.18/10.5.9/10.11.0

Timelineinfo

08/15/2025 CVE reserved
09/20/2025 +36 days Advisory disclosed
09/20/2025 +0 days VulDB entry created
10/02/2025 +12 days VulDB entry last update

Sourcesinfo

Advisory: mattermost.com
Researcher: daw10
Status: Confirmed

CVE: CVE-2025-9081 (🔒)
GCVE (CVE): GCVE-0-2025-9081
GCVE (VulDB): GCVE-100-325090
EUVD: 🔒
CNNVD: CNNVD-202509-3168 - Mattermost 安全漏洞

Entryinfo

Created: 09/20/2025 08:47
Updated: 10/02/2025 19:34
Changes: 09/20/2025 08:47 (64), 09/21/2025 06:36 (1), 09/22/2025 17:28 (6), 09/26/2025 01:24 (11), 10/02/2025 19:34 (2)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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