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TI-2023-01667 Aliases CVE-2023-1774GHSA-9hj7-v56g-rhf6

Unauthorized email invite to a private channel

Priority LOW 24CWE-862Published · Updated

Key facts

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

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and GitHub. Impact type from CWE-862.

Summary

When processing an email invite to a private channel on a team, Mattermost fails to validate the inviter's permission to that channel, allowing an attacker to invite themselves to a private channel.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00317 24th percentileScored 2026-11-07
Fix Fixed Mattermost (Mattermost): 7.7.2, 7.8.0, 7.1.6github.com/mattermost/mattermost-server (Go): 7.1.6, 7.7.2+2 more products

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 7.7.1; up to 7.1.5; before 7.8.07.7.2, 7.8.0, 7.1.6Patch availableCNA
—github.com/mattermost/mattermost-server (Go)3.3.0 to before 7.1.67.1.6Patch availableGHSA-9hj7-v56g-rhf6
—github.com/mattermost/mattermost-server (Go)7.7.0 to before 7.7.27.7.2Patch availableGHSA-9hj7-v56g-rhf6
—github.com/mattermost/mattermost-server (Go)7.1.0 to before 7.1.67.1.6Patch availableGHSA-9hj7-v56g-rhf6
—github.com/mattermost/mattermost-server/v5 (Go)5.0.0 to before 7.1.67.1.6Patch availableGHSA-9hj7-v56g-rhf6
—github.com/mattermost/mattermost-server/v6 (Go)6.0.0 to before 7.1.67.1.6Patch availableGHSA-9hj7-v56g-rhf6
  • Mattermost VendorMattermost Affected up to 7.7.1; up to 7.1.5; before 7.8.0 Fixed in 7.7.2, 7.8.0, 7.1.6 Patch available CNA
  • github.com/mattermost/mattermost-server (Go) Vendor— Affected 3.3.0 to before 7.1.6 Fixed in 7.1.6 Patch available GHSA-9hj7-v56g-rhf6
  • github.com/mattermost/mattermost-server (Go) Vendor— Affected 7.7.0 to before 7.7.2 Fixed in 7.7.2 Patch available GHSA-9hj7-v56g-rhf6
  • github.com/mattermost/mattermost-server (Go) Vendor— Affected 7.1.0 to before 7.1.6 Fixed in 7.1.6 Patch available GHSA-9hj7-v56g-rhf6
  • github.com/mattermost/mattermost-server/v5 (Go) Vendor— Affected 5.0.0 to before 7.1.6 Fixed in 7.1.6 Patch available GHSA-9hj7-v56g-rhf6
  • github.com/mattermost/mattermost-server/v6 (Go) Vendor— Affected 6.0.0 to before 7.1.6 Fixed in 7.1.6 Patch available GHSA-9hj7-v56g-rhf6

CPE configurations NVD · 2

CPEVersionsRoleVendor
cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*before 7.1.6VulnerableMattermost
cpe:2.3:a:mattermost:mattermost_server:7.7.1:*:*:*:*:*:*:*7.7.1VulnerableMattermost
  • cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:* Versions before 7.1.6 Vulnerable ·Mattermost
  • cpe:2.3:a:mattermost:mattermost_server:7.7.1:*:*:*:*:*:*:* Versions 7.7.1 Vulnerable ·Mattermost

Remediation

  • Fix · CNA Mattermost (Mattermost) Fixed in 7.7.2, 7.8.0, 7.1.6
  • Fix · GHSA-9hj7-v56g-rhf6 github.com/mattermost/mattermost-server (Go) Fixed in 7.1.6 Advisory →
  • Fix · GHSA-9hj7-v56g-rhf6 github.com/mattermost/mattermost-server (Go) Fixed in 7.7.2 Advisory →
  • Fix · GHSA-9hj7-v56g-rhf6 github.com/mattermost/mattermost-server (Go) Fixed in 7.1.6 Advisory →
  • Fix · GHSA-9hj7-v56g-rhf6 github.com/mattermost/mattermost-server/v5 (Go) Fixed in 7.1.6 Advisory →
  • Fix · GHSA-9hj7-v56g-rhf6 github.com/mattermost/mattermost-server/v6 (Go) Fixed in 7.1.6 Advisory →

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Release ·

    Mattermost 7.8.0

    3 records Highest priority Priority LOW 3 LOW

    Other records, highest priority first

    • TI-2023-01669 Stored XSS via SVG attachment on BoardsPriority LOW 34
    • TI-2023-01668 Unsanitized events sent over Websocket to regular users in a High Availability environmentPriority LOW 30
    Show all 3 records →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2023-1774
  2. 2026-10-03 Alias added: GHSA-9hj7-v56g-rhf6

References

Advisory 2

Other 1

  • TI-2025-18933 Arbitrary file read in Mattermost Boards via import & export board archive CVSS 3.1CRITICAL 9.9
  • TI-2025-04465 Path Traversal Leading to RCE by Any Authenticated Mattermost User CVSS 3.1CRITICAL 9.9
  • TI-2017-14068 An issue was discovered in Mattermost Server before 3.6.2. CVSS 3.1CRITICAL 9.8
  • TI-2017-14060 An issue was discovered in Mattermost Server before 3.8.2, 3.7.5, and 3.6.7. CVSS 3.1CRITICAL 9.8
  • TI-2017-14048 An issue was discovered in Mattermost Server before 4.1.0, 4.0.4, and 3.10.3. CVSS 3.1CRITICAL 9.8
  • TI-2025-14360 Arbitrary file read via block duplication in Mattermost Boards CVSS 3.1CRITICAL 9.9
See all 505 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences