ha-mcp has XSS via Unescaped HTML in OAuth Consent Form
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- Required
- Attack complexity
- High
- Impact type
- Cross-site scripting
- Confidentiality · integrity · availability
- High · High · None
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub. Impact type from CWE-79.
Summary
ha-mcp is a Home Assistant MCP Server. Prior to 7.0.0, the ha-mcp OAuth consent form renders user-controlled parameters via Python f-strings with no HTML escaping. An attacker who can reach the OAuth endpoint and convince the server operator to follow a crafted authorization URL could execute JavaScript in the operator's browser. This affects only users running the beta OAuth mode (ha-mcp-oauth), which is not part of the standard setup and requires explicit configuration. This vulnerability is fixed in 7.0.0.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Total
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 |
|---|---|---|---|---|---|
| homeassistant-ai | ha-mcp | before 7.0.0 | 7.0.0 | Patch available | CNA |
| — | ha-mcp (PyPI) | before 7.0.0 | 7.0.0 | Patch available | GHSA-pf93-j98v-25pv |
- ha-mcp Vendorhomeassistant-ai Affected before 7.0.0 Fixed in 7.0.0 Patch available CNA
- ha-mcp (PyPI) Vendor— Affected before 7.0.0 Fixed in 7.0.0 Patch available GHSA-pf93-j98v-25pv
CPE configurations NVD · 1
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:homeassistant-ai:home_assistant_mcp_server:*:*:*:*:*:*:*:* | before 7.0.0 | Vulnerable | homeassistant-ai |
- cpe:2.3:a:homeassistant-ai:home_assistant_mcp_server:*:*:*:*:*:*:*:* Versions before 7.0.0 Vulnerable ·homeassistant-ai
Remediation
- Fix · CNA ha-mcp (homeassistant-ai) Fixed in 7.0.0
- Fix · GHSA-pf93-j98v-25pv ha-mcp (PyPI) Fixed in 7.0.0 Advisory →
Timeline
- 2026-10-02 Threatist record created from CVE-2026-32112
- 2026-10-03 Alias added: GHSA-pf93-j98v-25pv
References
More homeassistant-ai Home Assistant Mcp Server vulnerabilities
- TI-2026-24649 ha-mcp OAuth 2.1 DCR mode enables network reconnaissance via an error oracle CVSS 3.1MEDIUM 5.3
Sources
- CVE-2026-32112 · CVE Program
- CVE-2026-32112 · NVD
- FIRST EPSS
- GHSA-pf93-j98v-25pv · 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