{"cve":{"cve_id":"CVE-2026-25640","is_kev":false,"kev_date_added":null,"kev_vendor_project":null,"kev_product":null,"kev_vulnerability_name":null,"kev_short_description":null,"kev_required_action":null,"kev_due_date":null,"kev_known_ransomware":null,"kev_notes":null,"kev_cwes":null,"epss_score":0.00269,"epss_percentile":0.18323,"epss_as_of":"2026-06-23","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.","published_at":"2026-02-06T20:01:53.892000Z","last_modified_at":null,"cvss_v3_score":7.1,"cvss_v3_vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N","cvss_v3_severity":"HIGH","cvss_v4_score":null,"cvss_v4_vector":null,"cvss_v4_severity":null,"ssvc_decision":null,"ssvc_exploitation":null,"ssvc_automatable":null,"ssvc_technical_impact":null,"cwes":["CWE-22","CWE-79"],"nvd_references":["https://github.com/pydantic/pydantic-ai/security/advisories/GHSA-wjp5-868j-wqv7","https://github.com/pydantic/pydantic-ai/releases/tag/v1.51.0"],"vuln_status":null,"trending_score":null,"is_trending":false,"has_trended":false,"trended_number_one":false,"trending_peak_score":null,"trending_peak_rank":null,"started_trending_at":null,"trended_number_one_at":null,"summary_generated":null,"summary_generated_at":null,"summary_model":null,"created_at":"2026-06-24T00:09:39.878444Z","updated_at":"2026-06-28T23:29:26.116204Z"},"effective_severity":"HIGH","badges":[],"impact_analysis":[],"cvss_v3_decoded":{"version":"3.1","metrics":[{"metric":"AV","name":"Attack Vector","value":"N","value_label":"Network"},{"metric":"AC","name":"Attack Complexity","value":"L","value_label":"Low"},{"metric":"PR","name":"Privileges Required","value":"N","value_label":"None"},{"metric":"UI","name":"User Interaction","value":"R","value_label":"Required"},{"metric":"S","name":"Scope","value":"U","value_label":"Unchanged"},{"metric":"C","name":"Confidentiality","value":"H","value_label":"High"},{"metric":"I","name":"Integrity","value":"L","value_label":"Low"},{"metric":"A","name":"Availability","value":"N","value_label":"None"}]},"cvss_v4_decoded":{"version":null,"metrics":[]},"affected":[{"vendor_slug":"pydantic","vendor_name":"pydantic","product_slug":"pydantic-ai","product_name":"pydantic-ai","version_start":">= 1.34.0, < 1.51.0","version_start_inclusive":true,"version_end":">= 1.34.0, < 1.51.0","version_end_inclusive":true,"cpe23_uri":"cve5:pydantic:pydantic-ai:>= 1.34.0, < 1.51.0:>= 1.34.0, < 1.51.0"}],"exploit_refs":[],"news":[],"references":[{"url":"https://github.com/pydantic/pydantic-ai/security/advisories/GHSA-wjp5-868j-wqv7","source_type":"VENDOR_ADVISORY","tags":["advisory"]},{"url":"https://github.com/pydantic/pydantic-ai/releases/tag/v1.51.0","source_type":"PATCH","tags":["patch"]}],"timeline":[{"type":"published","at":"2026-02-06T20:01:53.892000Z","label":"CVE published","source":null},{"type":"cvss_changed","at":"2026-06-28T17:52:12.012794Z","label":"CVSS score revised","source":"cvelistv5"},{"type":"cvss_changed","at":"2026-06-28T17:52:12.012794Z","label":"CVSS score revised","source":"cvelistv5"},{"type":"cvss_changed","at":"2026-06-28T17:52:12.012794Z","label":"CVSS score revised","source":"cvelistv5"}]}