Pydantic AI Web chat UI (`Agent.to_web()`, `clai web`): a website visited by the developer can trigger agent runs and server-side tool execution on the local chat endpoint

Not analysed yet

We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.

Severity and exploitation

• CISA KEV Not listed.
• EPSS 0.0016, the 4th percentile, on 5 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

Timeline

1. 31 Oct 2026, 14:08 UTC First seen by agentprime
2. 31 Oct 2026, 14:08 UTC Confirmed by OSV

Sources

• GitHub Advisory Database: GHSA-h4xc-3qfq-jf93
• OSV: GHSA-h4xc-3qfq-jf93
• github.com/pydantic/pydantic-ai/security/advisories/GHSA-h4xc-3qfq-jf93
• github.com/pydantic/pydantic-ai/pull/7382
• github.com/pydantic/pydantic-ai/pull/7383
• github.com/pydantic/pydantic-ai/commit/d2690201a1834005d382dbf5c47e0ed94ef8bf46
• github.com/pydantic/pydantic-ai/commit/dd2abbdfa029c9ad138e7cc0edd2eaeaf9ed69c0
• github.com/pydantic/pydantic-ai
• github.com/pydantic/pydantic-ai/releases/tag/v1.107.4
• github.com/pydantic/pydantic-ai/releases/tag/v2.28.0

Facts on this page come from the GitHub Advisory Database (CC-BY 4.0), OSV and the other sources listed, as published. We don’t reproduce full advisory descriptions, which can contain exploit code.