Insufficient token rotation validation in remote cluster invite confirmation
Priority LOW 19CWE-863Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Security bypass
- Confidentiality · integrity · availability
- None · Low · None
- Fix status
- Fixed
Attack profile from CVSS 3.1 · NVD. Fix status from CNA and GitHub. Impact type from CWE-863.
Summary
Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13 fail to validate that the RefreshedToken differs from the original invite token during remote cluster invite confirmation which allows an authenticated attacker to bypass token rotation and reuse the original invite token via sending a crafted invite confirmation with a RefreshedToken matching the original token. Mattermost Advisory ID: MMSA-2026-00575
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00142 3rd percentileScored 2026-11-07
Fix Fixed Mattermost (Mattermost): 11.6.0, 11.5.2, 10.11.14github.com/mattermost/mattermost/server/v8 (Go): 11.5.2, 10.11.14, 8.0.0-20260313190740-742e0be95074+1 more product
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
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Mattermost | Mattermost | 11.5.0 – 11.5.1; 10.11.0 – 10.11.13 | 11.6.0, 11.5.2, 10.11.14 | Patch available | CNA |
| — | github.com/mattermost/mattermost/server/v8 (Go) | 11.5.0 to before 11.5.2 | 11.5.2 | Patch available | GHSA-hqpj-f3jh-29vx |
| — | github.com/mattermost/mattermost/server/v8 (Go) | 10.11.0 to before 10.11.14 | 10.11.14 | Patch available | GHSA-hqpj-f3jh-29vx |
| — | github.com/mattermost/mattermost/server/v8 (Go) | before 8.0.0-20260313190740-742e0be95074 | 8.0.0-20260313190740-742e0be95074 | Patch available | GHSA-hqpj-f3jh-29vx |
| — | github.com/mattermost/mattermost-server (Go) | before 5.3.2-0.20260313190740-742e0be95074 | 5.3.2-0.20260313190740-742e0be95074 | Patch available | GHSA-hqpj-f3jh-29vx |
- Mattermost VendorMattermost Affected 11.5.0 – 11.5.1; 10.11.0 – 10.11.13 Fixed in 11.6.0, 11.5.2, 10.11.14 Patch available CNA
- github.com/mattermost/mattermost/server/v8 (Go) Vendor— Affected 11.5.0 to before 11.5.2 Fixed in 11.5.2 Patch available GHSA-hqpj-f3jh-29vx
- github.com/mattermost/mattermost/server/v8 (Go) Vendor— Affected 10.11.0 to before 10.11.14 Fixed in 10.11.14 Patch available GHSA-hqpj-f3jh-29vx
- github.com/mattermost/mattermost/server/v8 (Go) Vendor— Affected before 8.0.0-20260313190740-742e0be95074 Fixed in 8.0.0-20260313190740-742e0be95074 Patch available GHSA-hqpj-f3jh-29vx
- github.com/mattermost/mattermost-server (Go) Vendor— Affected before 5.3.2-0.20260313190740-742e0be95074 Fixed in 5.3.2-0.20260313190740-742e0be95074 Patch available GHSA-hqpj-f3jh-29vx
CPE configurations NVD · 1
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:* | 10.11.0 to before 10.11.14; 11.5.0 to before 11.5.2 | Vulnerable | Mattermost |
- cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:* Versions 10.11.0 to before 10.11.14; 11.5.0 to before 11.5.2 Vulnerable ·Mattermost
Remediation
- Fix · CNA Mattermost (Mattermost) Fixed in 11.6.0, 11.5.2, 10.11.14
- Fix · GHSA-hqpj-f3jh-29vx github.com/mattermost/mattermost/server/v8 (Go) Fixed in 11.5.2 Advisory →
- Fix · GHSA-hqpj-f3jh-29vx github.com/mattermost/mattermost/server/v8 (Go) Fixed in 10.11.14 Advisory →
- Fix · GHSA-hqpj-f3jh-29vx github.com/mattermost/mattermost/server/v8 (Go) Fixed in 8.0.0-20260313190740-742e0be95074 Advisory →
- Fix · GHSA-hqpj-f3jh-29vx github.com/mattermost/mattermost-server (Go) Fixed in 5.3.2-0.20260313190740-742e0be95074 Advisory →
Timeline
- 2026-10-02 Threatist record created from CVE-2026-4273
- 2026-10-03 Alias added: GHSA-hqpj-f3jh-29vx
References
More Mattermost Server vulnerabilities
- 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
Sources
- CVE-2026-4273 · CVE Program
- CVE-2026-4273 · NVD
- FIRST EPSS
- GHSA-hqpj-f3jh-29vx · GitHub Advisory Database · CC BY 4.0
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