7.6

CVE-2026-107295: `pydantic-ai-slim` web UI `/api/chat` accepts browser-simple cross-origin requests that can trigger agent tool execution

Analyzed
AliasesGHSA-h4xc-3qfq-jf93PYSEC-2026-4278PYSEC-2026-4287
Published 08-10-2026Last modified 08-10-2026

Vulnerability summary

CVE-2026-107295 is a high (CVSS 7.6) Cross-Site Request Forgery vulnerability in pydantic pydantic_ai. EPSS estimates a 0.16% chance of exploitation in the next 30 days, higher than 4.9% of scored vulnerabilities.

Priority
Routine

Not severe (CVSS 7.6, network access); no exploitation reported by the 5 checked sources

Source freshness unavailable

How is this decided?
CVSS score
7.6/10
010
High · v3.1 (CVE.org)
EPSS score
0.16%
0%100%
Low · Change unavailable
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded

Timeline

  1. 08-10-2026
    PublishedVulnerability first disclosed.
  2. 08-10-2026
    Last modifiedVulnerability information updated.

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 metrics

3 scores · 3 sources · 1 version

EPSS trend

Probability

0.16%

Chance of exploitation in the next 30 days

Percentile

5%

Versus all other CVEs

30-day change

Change unavailable

Change unavailable

09-10-202603-11-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Version check

Known conditions: network-reachable, no authentication, user interaction (CVSS vector). Other conditions: not stated in public data.

Pydantic3 products
PyPI2 products
  • pydantic-ai≥ 1.34.0, < 1.107.4 | ≥ 2.0.0b1, < 2.28.0
  • pydantic-ai-slim≥ 1.34.0, < 1.107.4 | ≥ 2.0.0b1, < 2.28.0

2 vendors · 5 products

References

12 links
Show all 12 references