Playbook run link to private channel grants channel access

published 2024-05-26 2 y ago modified 2026-06-17 4 mo ago also EUVD-2024-34458

cvss: 5.9; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.2%; EPSS 0.2% chance of exploitation in 30 days, percentile 13%
public exploits: 0; none known

Mattermost versions 9.5.x <= 9.5.3, 9.6.x <= 9.6.1, 8.1.x <= 8.1.12 fail to enforce proper access controls for channel and team membership when linking a playbook run to a channel which allows members to link their runs to private channels they were not members of.

Patch / fix

fixed in 1

Mattermost Mattermost 8.1.13, 9.5.4, 9.6.2, 9.7.0

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: partial
Assessed: 2 y ago (2024-06-07)

Exploit prediction

0.23% chance of exploitation in the next 30 days, higher than 13% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	5.9	CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:L/A:N

Affected products

Mattermost Mattermost

Classification

Weakness

CWE-284 Improper Access Control
CWE-639 Authorization Bypass Through User-Controlled Key

References

mattermost.com /security-updates
vendor-advisory

Sources

CVE List CVE-2024-32045
NVD CVE-2024-32045

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary