CVE-2026-32112 ha-mcp has XSS via Unescaped HTML in OAuth Consent Form
An attacker can execute JavaScript in the operator's browser via XSS in the OAuth consent form if beta OAuth mode is enabled.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-32112?
CVE-2026-32112 is a medium-severity cross-site scripting vulnerability in homeassistant-ai ha-mcp, published on 11 Mar 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
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.
Weakness: CWE-79
Which versions are affected by CVE-2026-32112?
3 open source packages ship an affected version, including ha-mcp. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
ha-mcp PyPI | All versions | 7.0.0 |
ha-mcp PyPI | All versions | 7.0.0 |
ha-mcp PyPI | All versions | 7.0.0 |
Products include Homeassistant-Ai Home Assistant Mcp Server.
How do I fix CVE-2026-32112?
Upgrade ha-mcp to 7.0.0 or later.
Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.
Is CVE-2026-32112 being exploited?
There is no known exploitation of CVE-2026-32112 in the wild and no public exploit code.
Other vulnerabilities in homeassistant-ai ha-mcp
Sources
Also known as GHSA-pf93-j98v-25pv, PYSEC-2026-2508.