SSRF (Server-Side Request Forgery) in pydantic-ai (CVE-2026-46678)
Summary
SSRF in pydantic-ai (CVE-2026-46678). Confidential information can be exposed externally. Exploitable via FileUrl. Mitigation: upgrade to 1.99.0 or later.
Original description
The description as published by the source.
Summary
When an application using Pydantic AI opts a URL into force_download='allow-local' (which disables 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). Dual-stack and translated networks route the IPv6 wrapper to the underlying IPv4 endpoint, exposing cloud IAM short-term credentials.
This is an incomplete fix of GHSA-2jrp-274c-jhv3 / CVE-2026-25580. The parent advisory's remediation guaranteed that "cloud metadata endpoints are always blocked, even with allow-local." That guarantee did not hold for IPv6-encoded forms of the metadata IPs.
Severity
Same impact metrics as the parent CVE, but materially narrower attack surface (AC:H instead of AC:L), because exploitation requires the application to have opted into allow-local on a URL influenced by untrusted input.
Who Is Affected
Applications are affected only if they explicitly opt for FileUrl (ImageUrl, AudioUrl, VideoUrl, DocumentUrl) into force_download='allow-local' on a URL that is, or could be, influenced by untrusted input.
Applications are not affected if they use any of the bundled integrations to ingest user input, because they do not propagate force_download from external data:
Agent.to_web/ `clai web…
Source: GitHub Security Advisories (Global) NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-46678 has been found in pydantic-ai.
Attackers can target a specific entry point like FileUrl over the network to misuse the product.
Confidential information can be exposed externally. CVSS score: 6.8/10.
What to do: upgrade pydantic-ai to 1.99.0 or later.
If unsure, ask your IT team or search "pydantic-ai CVE-2026-46678" on the vendor's site.
CVE-2026-46678 (pydantic-ai) — CWE-918 / CVSS v3 6.8
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Attack surface: FileUrl / ImageUrl / AudioUrl / VideoUrl
Patched: 1.99.0 — apply immediately
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
SSRF (CWE-918) exists in pydantic-ai. Attackers reach the vulnerable code path via FileUrl without authentication.
Check the vendor advisory for the affected versions of pydantic-ai. Attack surface: FileUrl / ImageUrl / AudioUrl / VideoUrl.
Severity: Medium (CVSS 6.8/10). Confidential information can be exposed externally.
Update to 1.99.0.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'pydantic-ai' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
grep -r 'pydantic-ai' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
pydantic-aiを grep し、稼働しているサービス・バージョンを把握する。 -
2Apply patch patch
Upgrade pydantic-ai to 1.99.0ステージング環境で 1.99.0 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
-
3Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Affected packages
References
- package github.com
- web github.com
- web github.com
- web github.com
- web security-advisories@github.com