MS Teams plugin sensitive config values not properly masked in support packets
Priority LOW 32CWE-200Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- High
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Information disclosure
- Confidentiality · integrity · availability
- High · Low · None
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub. Impact type from CWE-200.
Summary
Mattermost Plugins versions <=2.0.3.0 fail to properly mask sensitive configuration values which allows an attacker with access to support packets to obtain original plugin settings via exported configuration data. Mattermost Advisory ID: MMSA-2026-00606
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00187 8th percentileScored 2026-11-07
Fix Fixed Mattermost (Mattermost): 2.3.1.0github.com/mattermost/mattermost-plugin-msteams (Go): 1.15.1-0.20260102165339-036c761bd3cb
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 | up to 2.0.3 | 2.3.1.0 | Patch available | CNA |
| — | github.com/mattermost/mattermost-plugin-msteams (Go) | before 1.15.1-0.20260102165339-036c761bd3cb | 1.15.1-0.20260102165339-036c761bd3cb | Patch available | GHSA-4ppj-6chv-5pgc |
- Mattermost VendorMattermost Affected up to 2.0.3 Fixed in 2.3.1.0 Patch available CNA
- github.com/mattermost/mattermost-plugin-msteams (Go) Vendor— Affected before 1.15.1-0.20260102165339-036c761bd3cb Fixed in 1.15.1-0.20260102165339-036c761bd3cb Patch available GHSA-4ppj-6chv-5pgc
CPE configurations NVD · 1
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:mattermost:ms_teams:*:*:*:*:*:mattermost:*:* | before 2.3.1 | Vulnerable | Mattermost |
- cpe:2.3:a:mattermost:ms_teams:*:*:*:*:*:mattermost:*:* Versions before 2.3.1 Vulnerable ·Mattermost
Remediation
- Fix · CNA Mattermost (Mattermost) Fixed in 2.3.1.0
- Fix · GHSA-4ppj-6chv-5pgc github.com/mattermost/mattermost-plugin-msteams (Go) Fixed in 1.15.1-0.20260102165339-036c761bd3cb Advisory →
Timeline
- 2026-10-02 Threatist record created from CVE-2026-2476
- 2026-10-03 Alias added: GHSA-4ppj-6chv-5pgc
References
More Mattermost Ms Teams vulnerabilities
- TI-2025-20657 Webhook Secret Exposure via Timing attack in MSteams plugin CVSS 3.1MEDIUM 5.9
Sources
- CVE-2026-2476 · CVE Program
- CVE-2026-2476 · NVD
- FIRST EPSS
- GHSA-4ppj-6chv-5pgc · 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