An issue was discovered in Mattermost Desktop App before 4.4.0.
Priority LOW 32CWE-346Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Security bypass
- Confidentiality · integrity · availability
- Low · Low · Low
- Fix status
- No fix listed
Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-346.
Summary
An issue was discovered in Mattermost Desktop App before 4.4.0. The Same Origin Policy is mishandled during access-control decisions for web APIs, aka MMSA-2020-0006.
Why it matters now
EPSS 0.00425 37th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| — | — | all versions | — | No fix listed | CNA |
- — Vendor— Affected all versions Fixed in — No fix listed CNA
CPE configurations NVD · 1
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:mattermost:mattermost_desktop:*:*:*:*:*:*:*:* | before 4.4.0 | Vulnerable | Mattermost |
- cpe:2.3:a:mattermost:mattermost_desktop:*:*:*:*:*:*:*:* Versions before 4.4.0 Vulnerable ·Mattermost
Remediation
No fixed version listed by the sources yet.
Timeline
- 2026-10-02 Threatist record created from CVE-2020-14456
- 2026-10-03 Alias added: GHSA-w8pp-vvm7-4qqr
References
Advisory 1
More Mattermost Desktop vulnerabilities
- 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
Sources
- CVE-2020-14456 · CVE Program
- CVE-2020-14456 · NVD
- FIRST EPSS
- GHSA-w8pp-vvm7-4qqr · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences