SSRF in Pydantic Pydantic-Ai
CVE-2026-46678
Pydantic AI is a Python agent framework for building Generative AI applications. In versions 1.56.0 through 1.98.0, when an application opts a URL into force_download='allow-local' (disabling the default block on private/internal IPs), the cloud-metadata blocklist could be bypassed by encoding the metadata IP in an IPv6 transition form (IPv4-mapped IPv6, 6to4, or NAT64), exposing cloud IAM short-term credentials on dual-stack or translated networks. This is an incomplete fix of GHSA-2jrp-274c-jhv3 / CVE-2026-25580, whose remediation did not hold for IPv6-encoded forms of the metadata IPs. An application is affected only if it explicitly opts a FileUrl (ImageUrl, AudioUrl, VideoUrl, DocumentUrl) into force_download='allow-local' on a URL influenced by untrusted input; it is not affected when using bundled integrations to ingest user input (Agent.to_web / clai web, VercelAIAdapter, AGUIAdapter / Agent.to_ag_ui), since they do not propagate force_download from external data, nor when downloading only from developer-controlled URLs. This issue has been fixed in version 1.99.0.
Vulnerability class: SSRF (Server-Side Request Forgery)
EPSS: 0.004 (35.3th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 6.8 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:N/A:N.
Affected products
- Pydantic Pydantic-ai — versions >= 1.56.0, < 1.99.0
- Pydantic Pydantic_ai
- Pydantic Pydantic-ai-slim — versions >= 1.56.0, < 1.99.0
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_CONFIRM, Vendor Advisory)
- security-advisories@github.com (Product, x_refsource_MISC, Release Notes)
Frequently asked questions
- What is CVE-2026-46678?
- CVE-2026-46678 is a medium-severity vulnerability in Pydantic Pydantic-Ai, classified under Server-Side Request Forgery (SSRF). CVSS score: 6.8/10. Published 2026-07-29.
- How severe is CVE-2026-46678?
- Medium severity. CVSS v3 base score is 6.8 out of 10.