// For flags

CVE-2024-39777

Malicious remote can invite itself to an arbitrary local channel

Severity Score

8.7
*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

0
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

Track*
*SSVC
Descriptions

Mattermost versions 9.9.x <= 9.9.0, 9.5.x <= 9.5.6, 9.7.x <= 9.7.5 and 9.8.x <= 9.8.1 fail to disallow unsolicited invites to expose access to local channels, when shared channels are enabled, which allows a malicious remote to send an invite with the ID of an existing local channel, and that local channel will then become shared without the consent of the local admin.

Mattermost versions 9.9.x <= 9.9.0, 9.5.x <= 9.5.6, 9.7.x <= 9.7.5 and 9.8.x <= 9.8.1 fail to disallow unsolicited invites to expose access to local channels, when shared channels are enabled, which allows a malicious remote to send an invite with the ID of an existing local channel, and that local channel will then become shared without the consent of the local admin.

*Credits: Juho Forsén
CVSS Scores
Attack Vector
Network
Attack Complexity
Low
Privileges Required
High
User Interaction
None
Scope
Changed
Confidentiality
High
Integrity
High
Availability
None
Attack Vector
Network
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Changed
Confidentiality
High
Integrity
High
Availability
None
Attack Vector
Network
Attack Complexity
Low
Authentication
Single
Confidentiality
Complete
Integrity
Complete
Availability
None
* Common Vulnerability Scoring System
SSVC
  • Decision:Track*
Exploitation
None
Automatable
No
Tech. Impact
Total
* Organization's Worst-case Scenario
Timeline
  • 2024-07-23 CVE Reserved
  • 2024-08-01 CVE Published
  • 2024-08-01 CVE Updated
  • 2025-04-06 EPSS Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
  • ---------- First Exploit
CWE
  • CWE-284: Improper Access Control
CAPEC
References (1)
URL Tag Source
https://mattermost.com/security-updates
URL Date SRC
URL Date SRC
URL Date SRC
Affected Vendors, Products, and Versions
Vendor Product Version Other Status
Vendor Product Version Other Status <-- --> Vendor Product Version Other Status
Mattermost
Search vendor "Mattermost"
 Mattermost
Search vendor "Mattermost" for product "Mattermost"
 9.9.0
Search vendor "Mattermost" for product "Mattermost" and version "9.9.0"
en
Affected
Mattermost
Search vendor "Mattermost"
 Mattermost
Search vendor "Mattermost" for product "Mattermost"
 >= 9.5.0 <= 9.5.6
Search vendor "Mattermost" for product "Mattermost" and version " >= 9.5.0 <= 9.5.6"
en
Affected
Mattermost
Search vendor "Mattermost"
 Mattermost
Search vendor "Mattermost" for product "Mattermost"
 >= 9.7.0 <= 9.7.5
Search vendor "Mattermost" for product "Mattermost" and version " >= 9.7.0 <= 9.7.5"
en
Affected
Mattermost
Search vendor "Mattermost"
 Mattermost
Search vendor "Mattermost" for product "Mattermost"
 >= 9.8.0 <= 9.8.1
Search vendor "Mattermost" for product "Mattermost" and version " >= 9.8.0 <= 9.8.1"
en
Affected