{"answers":{"affected":"6 open source packages ship an affected version, including pydantic-ai and pydantic-ai-slim. It affects 1 product.","exploited":"There is no known exploitation of CVE-2026-25640 in the wild and no public exploit code.","fix":"Upgrade pydantic-ai to 1.51.0 or later.","what":"CVE-2026-25640 is a high-severity cross-site scripting vulnerability in pydantic-ai, published on 6 Feb 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link."},"fix_prompt":"Check this codebase for CVE-2026-25640 and fix it if it is affected.\n\nWhat it is: CVE-2026-25640 is a high-severity cross-site scripting vulnerability in pydantic-ai, published on 6 Feb 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.\nExploitation: There is no known exploitation of CVE-2026-25640 in the wild and no public exploit code.\n\nAffected packages and fixed versions:\n- pydantic-ai (PyPI): affected from 1.34.0; fixed in 1.51.0\n- pydantic-ai (PyPI): affected from 1.34.0; fixed in 1.51.0\n- pydantic-ai (PyPI): affected from 1.34.0; fixed in 1.51.0\n- pydantic-ai-slim (PyPI): affected from 1.34.0; fixed in 1.51.0\n- pydantic-ai-slim (PyPI): affected from 1.34.0; fixed in 1.51.0\n- pydantic-ai-slim (PyPI): affected from 1.34.0; fixed in 1.51.0\n\nTask:\n1. 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.\n2. 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.\n3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.\n4. Run the tests and summarise what changed and why.\n5. If nothing in the project is affected, say so and change nothing.\n\nReference: https://insights.sbomify.com/CVE-2026-25640/ (Markdown: https://insights.sbomify.com/CVE-2026-25640/index.md)","id":"CVE-2026-25640","markdown":"https://insights.sbomify.com/CVE-2026-25640/index.md","name":"CVE-2026-25640","record":{"aliases":["GHSA-wjp5-868j-wqv7","PYSEC-2026-2979","PYSEC-2026-2983"],"analysis":{"component_type":"library","fix_type":"upgrade","impacts":["code_execution","data_read"],"network_reachable":"yes","non_default_config":true,"product_category":"Python AI agent framework","requires_auth":"none","summary":"Attackers can execute arbitrary JavaScript in victims' browsers via path traversal in the web UI CDN URL, stealing chat history and client-side data.","user_interaction":"required","vuln_class":"xss"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"GitHub_M","cpe":[{"product":"pydantic_ai","vendor":"pydantic"}],"cvss":{"score":7.1,"severity":"high","source":"cna","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N","version":"3.1"},"cwes":[{"id":"CWE-79","name":"Improper Neutralization of Input During Web Page Generation"},{"id":"CWE-22","name":"Improper Limitation of a Pathname to a Restricted Directory"}],"description":"Pydantic AI is a Python agent framework for building applications and workflows with Generative AI. From 1.34.0 to before 1.51.0,  a path traversal vulnerability in the Pydantic AI web UI allows an attacker to serve arbitrary JavaScript in the context of the application by crafting a malicious URL. In affected versions, the CDN URL is constructed using a version query parameter from the request URL. This parameter is not validated, allowing path traversal sequences that cause the server to fetch and serve attacker-controlled HTML/JavaScript from an arbitrary source on the same CDN, instead of the legitimate chat UI package. If a victim clicks the link or visits it via an iframe, attacker-controlled code executes in their browser, enabling theft of chat history and other client-side data. This vulnerability only affects applications that use Agent.to_web to serve a chat interface and clai web to serve a chat interface from the CLI. These are typically run locally (on localhost), but may also be deployed on a remote server. This vulnerability is fixed in 1.51.0.","ecosystems":["PyPI"],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"none_known"},"has_fix":true,"headline":"Pydantic AI affected by Stored XSS via Path Traversal in Web UI CDN URL","id":"CVE-2026-25640","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"PyPI","product":null,"products":[],"type":"xss","year":"2026"},"n_packages":6,"n_references":2,"next":{"headline":"SandboxJS has a sandbox escape via TOCTOU bug on keys in property accesses","id":"CVE-2026-25641"},"packages":[{"ecosystem":"PyPI","fixed":["1.51.0"],"introduced":["1.34.0"],"last_affected":[],"package":"pydantic-ai","purl":null,"source":"GHSA-wjp5-868j-wqv7"},{"ecosystem":"PyPI","fixed":["1.51.0"],"introduced":["1.34.0"],"last_affected":[],"package":"pydantic-ai","purl":"pkg:pypi/pydantic-ai","source":"GHSA-wjp5-868j-wqv7"},{"ecosystem":"PyPI","fixed":["1.51.0"],"introduced":["1.34.0"],"last_affected":[],"package":"pydantic-ai","purl":"pkg:pypi/pydantic-ai","source":"PYSEC-2026-2979"},{"ecosystem":"PyPI","fixed":["1.51.0"],"introduced":["1.34.0"],"last_affected":[],"package":"pydantic-ai-slim","purl":null,"source":"GHSA-wjp5-868j-wqv7"},{"ecosystem":"PyPI","fixed":["1.51.0"],"introduced":["1.34.0"],"last_affected":[],"package":"pydantic-ai-slim","purl":"pkg:pypi/pydantic-ai-slim","source":"GHSA-wjp5-868j-wqv7"},{"ecosystem":"PyPI","fixed":["1.51.0"],"introduced":["1.34.0"],"last_affected":[],"package":"pydantic-ai-slim","purl":"pkg:pypi/pydantic-ai-slim","source":"PYSEC-2026-2983"}],"prev":{"headline":"Axios affected by Denial of Service via __proto__ Key in mergeConfig","id":"CVE-2026-25639"},"products":["pydantic-ai"],"published":"2026-02-06","related":[{"cvss_score":8.6,"headline":"Pydantic AI Affected by Server-Side Request Forgery (SSRF) in URL Download Handling","id":"CVE-2026-25580","kev_date_added":null,"published":"2026-02-06"},{"cvss_score":7.6,"headline":"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","id":"CVE-2026-107295","kev_date_added":null,"published":"2026-10-08"},{"cvss_score":7.5,"headline":"Pydantic AI: Concurrency-limited models can keep their slot when a streamed request ends early","id":"CVE-2026-107286","kev_date_added":null,"published":"2026-10-08"},{"cvss_score":6.8,"headline":"Pydantic AI: SSRF cloud-metadata blocklist bypass via IPv6 zone identifiers","id":"CVE-2026-107289","kev_date_added":null,"published":"2026-10-08"},{"cvss_score":6.8,"headline":"Pydantic AI: SSRF cloud-metadata blocklist bypass via IPv4-mapped IPv6 (Incomplete fix of CVE-2026-25580)","id":"CVE-2026-46678","kev_date_added":null,"published":"2026-07-29"},{"cvss_score":6.8,"headline":"Pydantic AI: Unvalidated UploadedFile references in UI adapters allow server-side file access using the application's credentials","id":"CVE-2026-54249","kev_date_added":null,"published":"2026-07-29"}],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"CC BY 4.0","name":"GitHub Advisory Database","prefix":"GHSA"},{"class":"attribution","licence":"CC BY 4.0","name":"PyPA Advisory Database","prefix":"PYSEC"},{"class":"attribution","licence":"US public information, NVD API terms","name":"NVD"},{"class":"attribution","licence":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":"no","exploitation":"none","technical_impact":"partial"},"state":"PUBLISHED","updated":"2026-07-15","vendors":["pydantic"]},"summary":"Attackers can execute arbitrary JavaScript in victims' browsers via path traversal in the web UI CDN URL, stealing chat history and client-side data.","url":"https://insights.sbomify.com/CVE-2026-25640/"}