CVE-2026-107295
From 1.34.0 until 1.107.4 and 2.28.0, the Agent.to_web() and clai web development chat endpoint has missing request content-type validation.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.16%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
Pydantic AI is a Python agent framework for building applications and workflows with Generative AI. From 1.34.0 until 1.107.4 and 2.28.0, the Agent.to_web() and clai web development chat endpoint has missing request content-type validation. A website visited by a developer can submit a browser-compatible request to a loopback-hosted chat server, causing the served agent to run and execute tools with the privileges and credentials of the local process; client-relayed approval decisions also leave requires_approval=True tools exposed. Binding to localhost does not prevent a browser page from reaching the loopback address. This issue is fixed in versions 1.107.4 and 2.28.0.
- CVSS 3.1
- 7.6 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:H/A:L
- EPSS
- 0.16% probability · 5th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-352
- Affected
- pydantic/pydantic ai
- Source
- security-advisories@github.com
EPSS moved from 0.2% on 9 October 2026 to 0.2% on 26 October 2026.
References
- https://github.com/pydantic/pydantic-ai/commit/d2690201a1834005d382dbf5c47e0ed94ef8bf46Patch
- https://github.com/pydantic/pydantic-ai/commit/dd2abbdfa029c9ad138e7cc0edd2eaeaf9ed69c0Patch
- https://github.com/pydantic/pydantic-ai/pull/7382Patch, Issue Tracking
- https://github.com/pydantic/pydantic-ai/pull/7383Patch, Issue Tracking
- https://github.com/pydantic/pydantic-ai/releases/tag/v1.107.4Patch, Release Notes
- https://github.com/pydantic/pydantic-ai/releases/tag/v2.28.0Patch, Release Notes
- https://github.com/pydantic/pydantic-ai/security/advisories/GHSA-h4xc-3qfq-jf93Mitigation, Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.