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TI-2024-26690 Aliases CVE-2024-39772GHSA-5777-rcjj-9p22

Silent Desktop Screenshot Capture

Priority LOW 24CWE-284Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Security bypass
Confidentiality · integrity · availability
Low · None · None
Fix status
Fixed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and GitHub. Impact type from CWE-284.

Summary

Mattermost Desktop App versions <=5.8.0 fail to safeguard screen capture functionality which allows an attacker to silently capture high-quality screenshots via JavaScript APIs.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00312 24th percentileScored 2026-11-07
Fix Fixed Mattermost (Mattermost): 5.9.0mattermost-desktop (npm): 5.9.0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
MattermostMattermostup to 5.8.05.9.0Patch availableCNA
—mattermost-desktop (npm)before 5.9.05.9.0Patch availableGHSA-5777-rcjj-9p22
  • Mattermost VendorMattermost Affected up to 5.8.0 Fixed in 5.9.0 Patch available CNA
  • mattermost-desktop (npm) Vendor— Affected before 5.9.0 Fixed in 5.9.0 Patch available GHSA-5777-rcjj-9p22

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:mattermost:mattermost_desktop:*:*:*:*:*:*:*:*before 5.9.0VulnerableMattermost
  • cpe:2.3:a:mattermost:mattermost_desktop:*:*:*:*:*:*:*:* Versions before 5.9.0 Vulnerable ·Mattermost

Remediation

  • Fix · CNA Mattermost (Mattermost) Fixed in 5.9.0
  • Fix · GHSA-5777-rcjj-9p22 mattermost-desktop (npm) Fixed in 5.9.0 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2024-39772
  2. 2026-10-03 Alias added: GHSA-5777-rcjj-9p22

References

  • TI-2019-15074 An issue was discovered in Mattermost Desktop App before 4.3.0 on macOS. CVSS 3.1CRITICAL 9.8
  • TI-2016-09099 An issue was discovered in Mattermost Desktop App before 3.4.0. CVSS 3.1CRITICAL 9.8
  • TI-2019-15079 An issue was discovered in Mattermost Desktop App before 4.2.2. CVSS 3.1HIGH 8.8
  • TI-2024-26542 RCE in desktop app in Windows by local attacker CVSS 3.1HIGH 7.8
  • TI-2026-05712 Mattermost Desktop App fails to restrict the allow list of domains which NTLM credentials are passed CVSS 3.1HIGH 7.7
  • TI-2026-00781 Arbitrary application execution via unvalidated server-controlled URLs in Help menu CVSS 3.1HIGH 7.6
See all 33 →

Sources