VDB-273388 · CVE-2024-39839 · GCVE-0-2024-39839

Mattermost up to 9.5.6/9.7.5/9.8.1 Shared Channel access control

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
4.6	$0-$5k	0.00

Summaryinfo

A vulnerability labeled as critical has been found in Mattermost up to 9.5.6/9.7.5/9.8.1. Impacted is an unknown function of the component Shared Channel Handler. Executing a manipulation can lead to access control. This vulnerability appears as CVE-2024-39839. The attack may be performed from remote. There is no available exploit. The affected component should be upgraded.

Detailsinfo

A vulnerability has been found in Mattermost up to 9.5.6/9.7.5/9.8.1 and classified as critical. This vulnerability affects an unknown part of the component Shared Channel Handler. The manipulation with an unknown input leads to a access control vulnerability. The CWE definition for the vulnerability is CWE-284. The product does not restrict or incorrectly restricts access to a resource from an unauthorized actor. As an impact it is known to affect integrity, and availability. CVE summarizes:

Mattermost versions 9.9.x <= 9.9.0, 9.5.x <= 9.5.6, 9.7.x <= 9.7.5, 9.8.x <= 9.8.1 fail to disallow users to set their own remote username, when shared channels were enabled, which allows a user on a remote to set their remote username prop to an arbitrary string, which would be then synced to the local server as long as the user hadn't been synced before.

The weakness was presented by Juho Forsén. The advisory is shared for download at mattermost.com. This vulnerability was named CVE-2024-39839 since 07/23/2024. The exploitation appears to be easy. The attack can be initiated remotely. There are neither technical details nor an exploit publicly available. The MITRE ATT&CK project declares the attack technique as T1068.

Upgrading to version 9.5.7, 9.7.6, 9.8.2, 9.9.1 or 9.10.0 eliminates this vulnerability.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

Groupware Software

Name

Mattermost

Version

License

open-source

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.7
VulDB Meta Temp Score: 4.6

VulDB Base Score: 5.4
VulDB Temp Score: 5.2
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 4.3
NVD Vector: 🔍

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

CVSSv2info

AV	AC	Au	C	I	A
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💳	💳	💳	💳	💳	💳
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Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
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Unlock	Unlock	Unlock	Unlock	Unlock	Unlock

VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Access control
CWE: CWE-284 / 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-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Mattermost 9.5.7/9.7.6/9.8.2/9.9.1/9.10.0

Timelineinfo

07/23/2024 🔍
08/01/2024 +9 days 🔍
08/01/2024 +0 days 🔍
09/04/2024 +34 days 🔍

Sourcesinfo

Advisory: mattermost.com
Researcher: Juho Forsén
Status: Confirmed

CVE: CVE-2024-39839 (🔍)
GCVE (CVE): GCVE-0-2024-39839
GCVE (VulDB): GCVE-100-273388

Entryinfo

Created: 08/01/2024 16:48
Updated: 09/04/2024 20:25
Changes: 08/01/2024 16:48 (64), 09/04/2024 20:25 (13)
Complete: 🔍
Cache ID: 216::103