{"id":"GHSA-v36g-jcw9-x7cw","summary":"Pydantic AI: Excessive resource use when local web fetching converts nested HTML","details":"### Summary\n\nApplications using Pydantic AI's local web-fetch tool can experience excessive CPU and memory use when it converts attacker-controlled HTML. An agent must fetch the affected page; provider-native web fetching is not affected.\n\n### Details\n\nNested block elements cause HTML-to-Markdown conversion to reprocess accumulated text at each level and can greatly expand the intermediate output. The response-body limit bounds downloaded bytes, while the returned-content limit is applied only after conversion. On current releases, conversion runs in a worker thread but can still consume substantial resources and delay other work in the process. Older releases performed conversion on the event loop.\n\n### Mitigation\n\nUpgrade to a patched release of `pydantic-ai` or `pydantic-ai-slim`. If you cannot upgrade yet, avoid using local web fetching for attacker-controlled HTML.","aliases":["CVE-2026-107287"],"modified":"2026-10-08T18:00:09.891864929Z","published":"2026-10-08T17:40:50Z","database_specific":{"nvd_published_at":null,"cwe_ids":["CWE-400","CWE-407"],"severity":"MODERATE","github_reviewed":true,"github_reviewed_at":"2026-10-08T17:40:50Z"},"references":[{"type":"WEB","url":"https://github.com/pydantic/pydantic-ai/security/advisories/GHSA-v36g-jcw9-x7cw"},{"type":"WEB","url":"https://github.com/pydantic/pydantic-ai/pull/8984"},{"type":"WEB","url":"https://github.com/pydantic/pydantic-ai/pull/8985"},{"type":"WEB","url":"https://github.com/pydantic/pydantic-ai/commit/2b247add4950bef61d352e7ca8aefbd20539180c"},{"type":"WEB","url":"https://github.com/pydantic/pydantic-ai/commit/2fd38792693da00a3ca5412aeffb436787af3545"},{"type":"PACKAGE","url":"https://github.com/pydantic/pydantic-ai"},{"type":"WEB","url":"https://github.com/pydantic/pydantic-ai/releases/tag/v1.107.7"},{"type":"WEB","url":"https://github.com/pydantic/pydantic-ai/releases/tag/v2.52.0"}],"affected":[{"package":{"name":"pydantic-ai","ecosystem":"PyPI","purl":"pkg:pypi/pydantic-ai"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"1.77.0"},{"fixed":"1.107.7"}]}],"versions":["1.100.0","1.101.0","1.102.0","1.103.0","1.104.0","1.105.0","1.106.0","1.107.0","1.107.1","1.107.2","1.107.4","1.107.5","1.107.6","1.77.0","1.78.0","1.79.0","1.80.0","1.81.0","1.82.0","1.83.0","1.84.0","1.84.1","1.85.0","1.85.1","1.86.0","1.86.1","1.87.0","1.88.0","1.89.0","1.89.1","1.90.0","1.91.0","1.92.0","1.93.0","1.94.0","1.95.0","1.95.1","1.96.0","1.96.1","1.97.0","1.98.0","1.99.0"],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/10/GHSA-v36g-jcw9-x7cw/GHSA-v36g-jcw9-x7cw.json"}},{"package":{"name":"pydantic-ai","ecosystem":"PyPI","purl":"pkg:pypi/pydantic-ai"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"2.0.0b1"},{"fixed":"2.52.0"}]}],"versions":["2.0.0","2.0.0b1","2.0.0b2","2.0.0b3","2.0.0b4","2.0.0b5","2.0.0b6","2.0.0b7","2.1.0","2.10.0","2.11.0","2.12.0","2.13.0","2.14.0","2.14.1","2.15.0","2.16.0","2.17.0","2.18.0","2.19.0","2.2.0","2.20.0","2.21.0","2.22.0","2.23.0","2.24.0","2.25.0","2.26.0","2.27.0","2.27.1","2.28.0","2.29.0","2.3.0","2.30.0","2.31.0","2.31.1","2.32.0","2.32.1","2.32.2","2.33.0","2.34.0","2.35.0","2.35.1","2.35.3","2.36.0","2.37.0","2.38.0","2.39.0","2.4.0","2.40.0","2.41.0","2.42.0","2.43.0","2.44.0","2.45.0","2.46.0","2.47.0","2.48.0","2.49.0","2.5.0","2.5.1","2.50.0","2.51.0","2.6.0","2.7.0","2.8.0","2.9.0","2.9.1"],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/10/GHSA-v36g-jcw9-x7cw/GHSA-v36g-jcw9-x7cw.json"}},{"package":{"name":"pydantic-ai-slim","ecosystem":"PyPI","purl":"pkg:pypi/pydantic-ai-slim"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"1.77.0"},{"fixed":"1.107.7"}]}],"versions":["1.100.0","1.101.0","1.102.0","1.103.0","1.104.0","1.105.0","1.106.0","1.107.0","1.107.1","1.107.2","1.107.4","1.107.5","1.107.6","1.77.0","1.78.0","1.79.0","1.80.0","1.81.0","1.82.0","1.83.0","1.84.0","1.84.1","1.85.0","1.85.1","1.86.0","1.86.1","1.87.0","1.88.0","1.89.0","1.89.1","1.90.0","1.91.0","1.92.0","1.93.0","1.94.0","1.95.0","1.95.1","1.96.0","1.96.1","1.97.0","1.98.0","1.99.0"],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/10/GHSA-v36g-jcw9-x7cw/GHSA-v36g-jcw9-x7cw.json"}},{"package":{"name":"pydantic-ai-slim","ecosystem":"PyPI","purl":"pkg:pypi/pydantic-ai-slim"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"2.0.0b1"},{"fixed":"2.52.0"}]}],"versions":["2.0.0","2.0.0b1","2.0.0b2","2.0.0b3","2.0.0b4","2.0.0b5","2.0.0b6","2.0.0b7","2.1.0","2.10.0","2.11.0","2.12.0","2.13.0","2.14.0","2.14.1","2.15.0","2.16.0","2.17.0","2.18.0","2.19.0","2.2.0","2.20.0","2.21.0","2.22.0","2.23.0","2.24.0","2.25.0","2.26.0","2.27.0","2.27.1","2.28.0","2.29.0","2.3.0","2.30.0","2.31.0","2.31.1","2.32.0","2.32.1","2.32.2","2.33.0","2.34.0","2.35.0","2.35.1","2.35.3","2.36.0","2.37.0","2.38.0","2.39.0","2.4.0","2.40.0","2.41.0","2.42.0","2.43.0","2.44.0","2.45.0","2.46.0","2.47.0","2.48.0","2.49.0","2.5.0","2.5.1","2.50.0","2.51.0","2.6.0","2.7.0","2.8.0","2.9.0","2.9.1"],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/10/GHSA-v36g-jcw9-x7cw/GHSA-v36g-jcw9-x7cw.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H"}]}