# CVE-2026-48782: pydantic-ai: SSRF blocklist bypass via IPv4-compatible, SIIT/IVI, and local NAT64 IPv6 addresses (incomplete fix of CVE-2026-46678) > Attackers can bypass SSRF protections to access cloud metadata and steal IAM credentials via IPv6 transition forms in Pydantic AI. - **Severity:** Medium 6.8 (`CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:N/A:N`) - **Exploited in the wild:** Not known - **Login needed:** Not needed - **Attackable:** Over the internet - **Victim action needed:** Not needed - **Fix available:** Yes - **Published:** 16 Jun 2026 - **Updated:** 17 Jun 2026 - **Also known as:** GHSA-cg7w-rg45-pc59, PYSEC-2026-2977, PYSEC-2026-2981, ROOT-APP-PYPI-CVE-2026-48782 ## What is CVE-2026-48782? CVE-2026-48782 is a medium-severity server-side request forgery vulnerability in pydantic-ai, published on 16 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim. ### Official description Pydantic AI is a Python agent framework for building applications and workflows with Generative AI. In versions 1.56.0 through 1.101.0, 2.0.0b1, and 2.0.0b2, the cloud-metadata blocklist could be bypassed by encoding the metadata IP in an IPv6 transition form that the previous fix, CVE-2026-46678, did not decode, exposing cloud IAM short-term credentials. The previous remediation decoded only IPv4-mapped IPv6, 6to4, and the NAT64 well-known prefix, so the metadata guarantee did not hold for the remaining transition forms: IPv4-compatible IPv6 (::a.b.c.d), the NAT64 RFC 8215 local-use prefix (64:ff9b:1::/48), operator-chosen NAT64 prefixes, and ISATAP. The IPv6 wrapper is then delivered to the underlying IPv4 metadata endpoint. This occurs when an application using Pydantic AI opts a URL into force_download='allow-local' (which disables the default block on private/internal IPs) and runs on a network that actually routes the affected IPv6 transition forms: NAT64-configured networks (IPv6-only or dual-stack-with-NAT64 deployments, including some Kubernetes setups) for the NAT64 variants, or networks with an ISATAP tunnel for ISATAP. A standard dual-stack cloud VM or container does not route these forms and is not affected in practice. The IPv4-compatible and Teredo variants are deprecated and addressed as defense-in-depth. This is an incomplete fix of GHSA-cqp8-fcvh-x7r3 / CVE-2026-46678 (itself a follow-up to CVE-2026-25580). This issue has been fixed in version 2.0.0b3. Weakness: CWE-918 (Server-Side Request Forgery) ## Which versions are affected by CVE-2026-48782? 10 open source packages ship an affected version, including pydantic-ai and pydantic-ai-slim. It affects 1 product. | Package | Ecosystem | Affected | Fixed in | | --- | --- | --- | --- | | `pydantic-ai` | PyPI | From 1.56.0 | 1.102.0, 2.0.0b3 | | `pydantic-ai` | PyPI | From 1.56.0 | 1.102.0 | | `pydantic-ai` | PyPI | From 1.56.0 | 1.102.0 | | `pydantic-ai` | PyPI | From 2.0.0b1 | 2.0.0b3 | | `pydantic-ai` | PyPI | From 2.0.0b1 | 2.0.0b3 | | `pydantic-ai-slim` | PyPI | From 1.56.0 | 1.102.0, 2.0.0b3 | | `pydantic-ai-slim` | PyPI | From 1.56.0 | 1.102.0 | | `pydantic-ai-slim` | PyPI | From 1.56.0 | 1.102.0 | | `pydantic-ai-slim` | PyPI | From 2.0.0b1 | 2.0.0b3 | | `pydantic-ai-slim` | PyPI | From 2.0.0b1 | 2.0.0b3 | Products: Pydantic Pydantic Ai. ## How do I fix CVE-2026-48782? Upgrade pydantic-ai to a fixed version for your release line: 1.102.0 or 2.0.0b3. ## Is CVE-2026-48782 being exploited? There is no known exploitation of CVE-2026-48782 in the wild and no public exploit code. ## Other vulnerabilities in pydantic-ai - [CVE-2026-25580](https://insights.sbomify.com/CVE-2026-25580/): Pydantic AI Affected by Server-Side Request Forgery (SSRF) in URL Download Handling (high 8.6) - [CVE-2026-107295](https://insights.sbomify.com/CVE-2026-107295/): 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 (high 7.6) - [CVE-2026-107286](https://insights.sbomify.com/CVE-2026-107286/): Pydantic AI: Concurrency-limited models can keep their slot when a streamed request ends early (high 7.5) - [CVE-2026-25640](https://insights.sbomify.com/CVE-2026-25640/): Pydantic AI affected by Stored XSS via Path Traversal in Web UI CDN URL (high 7.1) - [CVE-2026-107289](https://insights.sbomify.com/CVE-2026-107289/): Pydantic AI: SSRF cloud-metadata blocklist bypass via IPv6 zone identifiers (medium 6.8) ## Fix prompt for AI coding agents ```text Check this codebase for CVE-2026-48782 and fix it if it is affected. What it is: CVE-2026-48782 is a medium-severity server-side request forgery vulnerability in pydantic-ai, published on 16 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim. Exploitation: There is no known exploitation of CVE-2026-48782 in the wild and no public exploit code. Affected packages and fixed versions: - pydantic-ai (PyPI): affected from 1.56.0; fixed in 1.102.0, 2.0.0b3 - pydantic-ai (PyPI): affected from 1.56.0; fixed in 1.102.0 - pydantic-ai (PyPI): affected from 1.56.0; fixed in 1.102.0 - pydantic-ai (PyPI): affected from 2.0.0b1; fixed in 2.0.0b3 - pydantic-ai (PyPI): affected from 2.0.0b1; fixed in 2.0.0b3 - pydantic-ai-slim (PyPI): affected from 1.56.0; fixed in 1.102.0, 2.0.0b3 - pydantic-ai-slim (PyPI): affected from 1.56.0; fixed in 1.102.0 - pydantic-ai-slim (PyPI): affected from 1.56.0; fixed in 1.102.0 - pydantic-ai-slim (PyPI): affected from 2.0.0b1; fixed in 2.0.0b3 - pydantic-ai-slim (PyPI): affected from 2.0.0b1; fixed in 2.0.0b3 Task: 1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies. 2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it. 3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead. 4. Run the tests and summarise what changed and why. 5. If nothing in the project is affected, say so and change nothing. Reference: https://insights.sbomify.com/CVE-2026-48782/ (Markdown: https://insights.sbomify.com/CVE-2026-48782/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2026-48782 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-48782 - OSV: https://osv.dev/vulnerability/CVE-2026-48782 --- From sbomify Insights: https://insights.sbomify.com/CVE-2026-48782/ Summaries are generated and may contain mistakes; the official description above is the record.