{"action":"Upgrade h2 to 4.3.0 or later.","affected":[{"fixed":"4.3.0","introduced":"0"}],"component":"h2","cve_ids":["CVE-2025-57804"],"ecosystem":"PyPI","epss":0.01795,"exploited":false,"fixed_versions":["4.3.0"],"ghsa_id":"GHSA-847f-9342-265h","id":"tcs_01M5KGSK6Y1Z078XKMVPD4VFDK","modified_at":"2026-07-07T17:47:39.182570446Z","published_at":"2026-07-07T16:03:01.951354Z","references":["https://osv.dev/vulnerability/PYSEC-2026-1435","https://github.com/python-hyper/h2/security/advisories/GHSA-847f-9342-265h","https://nvd.nist.gov/vuln/detail/CVE-2025-57804","https://github.com/python-hyper/h2/commit/035e9899f95e3709af098f578bfc3cd302298e3a","https://github.com/python-hyper/h2","https://lists.debian.org/debian-lts-announce/2025/09/msg00004.html","https://pypi.org/project/h2","https://github.com/advisories/GHSA-847f-9342-265h"],"severity":{"label":"medium","score":6.9},"sources":[{"source":"osv","source_id":"PYSEC-2026-1435","url":"https://osv.dev/vulnerability/PYSEC-2026-1435"},{"source":"nvd","source_id":"CVE-2025-57804","url":"https://nvd.nist.gov/vuln/detail/CVE-2025-57804"}],"summary":"h2 allows HTTP Request Smuggling due to illegal characters in headers"}