Mattermost Server up to 4.10.5/5.5.2/5.6.3/5.7.0 API Permission permission assignment

entryeditHistoryDiffjsonxmlCTI

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.
5.1	$0-$5k	0.00

A vulnerability, which was classified as critical, was found in Mattermost Server up to 4.10.5/5.5.2/5.6.3/5.7.0. This affects an unknown function of the component API Permission Handler. The manipulation with an unknown input leads to a privilege escalation vulnerability. CWE is classifying the issue as CWE-732. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

An issue was discovered in Mattermost Server before 5.7.1, 5.6.4, 5.5.3, and 4.10.6. It does not honor flags API permissions when deciding whether a user can receive intra-team posts.

The weakness was disclosed 06/19/2020 (Website). The advisory is shared at mattermost.com. This vulnerability is uniquely identified as CVE-2019-20887 since 06/19/2020. The exploitability is told to be easy. It is possible to initiate the attack remotely. The successful exploitation requires a authentication. Neither technical details nor an exploit are publicly available.

Upgrading to version 4.10.6, 5.5.3, 5.6.4 or 5.7.1 eliminates this vulnerability.

The entries 156956, 156957, 156958 and 156959 are pretty similar.

Productinfoedit

Name

Mattermost Server

CPE 2.3infoedit

CPE 2.2infoedit

CVSSv3infoedit

VulDB Meta Base Score: 5.3
VulDB Meta Temp Score: 5.1

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

NVD Base Score: 4.3
NVD Vector: 🔒

CVSSv2infoedit

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
unlock	unlock	unlock	unlock	unlock	unlock
unlock	unlock	unlock	unlock	unlock	unlock

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

NVD Base Score: 🔒

Exploitinginfoedit

Class: Privilege escalation
CWE: CWE-732
ATT&CK: Unknown

Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

Price Prediction: 🔍
Current Price Estimation: 🔒

0-Day	unlock	unlock	unlock	unlock
Today	unlock	unlock	unlock	unlock

Threat Intelligenceinfoedit

Threat: 🔍
Adversaries: 🔍
Geopolitics: 🔍
Economy: 🔍
Predictions: 🔍
Remediation: 🔍

Countermeasuresinfoedit

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Mattermost Server 4.10.6/5.5.3/5.6.4/5.7.1

Timelineinfoedit

06/19/2020 Advisory disclosed
06/19/2020 +0 days CVE assigned
06/20/2020 +1 days VulDB entry created
10/25/2020 +127 days VulDB last update

Sourcesinfoedit

Advisory: mattermost.com
Status: Not defined
Confirmation: 🔒

CVE: CVE-2019-20887 (🔒)
See also: 🔒

Entryinfoedit

Created: 06/20/2020 08:03 AM
Updated: 10/25/2020 07:27 PM
Changes: (1) advisory_confirm_url
Complete: 🔍