{"id":"CVE-2026-84379","state":"PUBLISHED","title":"HTTPX2: Multipart part header injection via unvalidated file Content-Type and custom headers","description":"HTTPX2 is a next generation HTTP client for Python. Prior to 2.11.0, FileField.render_headers() in src/httpx2/httpx2/_multipart.py directly interpolates attacker-controlled content_type values and custom headers from the files= three-element (filename, content, content_type) tuple and the files= four-element (filename, content, content_type, headers) tuple into multipart/form-data part headers without validating header names or values. CR or LF characters can terminate a part header, inject additional part headers, or end the part header block early, allowing a downstream multipart parser to treat attacker-supplied lines as genuine headers and potentially alter part semantics or bypass header-based checks. This issue is fixed in version 2.11.0.","publishedAt":"2026-09-02T17:57:17.092Z","updatedAt":"2026-09-02T18:20:46.599Z","severity":{"score":5.3,"label":"Medium","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","source":"GitHub_M"},"assigner":"GitHub_M","products":["pydantic httpx2"],"affected":[{"vendor":"pydantic","product":"httpx2","versions":[{"version":"< 2.11.0","status":"affected"}]}],"references":["https://github.com/pydantic/httpx2/security/advisories/GHSA-h4x7-gw46-3wm6","https://github.com/pydantic/httpx2/pull/1142","https://github.com/pydantic/httpx2/commit/de96d810ee4e309d118982fe7084a46a2bcd600d","https://github.com/pydantic/httpx2/releases/tag/v2.11.0"],"weaknesses":["CWE-93"],"ingestedAt":"2026-10-29T20:13:15.269Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/84xxx/CVE-2026-84379.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-84379","state":"PUBLISHED","datePublished":"2026-09-02T17:57:17.092Z","dateUpdated":"2026-09-02T18:20:46.599Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-09-01T16:27:58.130Z"},"containers":{"cna":{"title":"HTTPX2: Multipart part header injection via unvalidated file Content-Type and custom headers","descriptions":[{"lang":"en","value":"HTTPX2 is a next generation HTTP client for Python. Prior to 2.11.0, FileField.render_headers() in src/httpx2/httpx2/_multipart.py directly interpolates attacker-controlled content_type values and custom headers from the files= three-element (filename, content, content_type) tuple and the files= four-element (filename, content, content_type, headers) tuple into multipart/form-data part headers without validating header names or values. CR or LF characters can terminate a part header, inject additional part headers, or end the part header block early, allowing a downstream multipart parser to treat attacker-supplied lines as genuine headers and potentially alter part semantics or bypass header-based checks. This issue is fixed in version 2.11.0."}],"affected":[{"vendor":"pydantic","product":"httpx2","versions":[{"version":"< 2.11.0","status":"affected"}]}],"references":[{"url":"https://github.com/pydantic/httpx2/security/advisories/GHSA-h4x7-gw46-3wm6","name":"https://github.com/pydantic/httpx2/security/advisories/GHSA-h4x7-gw46-3wm6","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/pydantic/httpx2/pull/1142","name":"https://github.com/pydantic/httpx2/pull/1142","tags":["x_refsource_MISC"]},{"url":"https://github.com/pydantic/httpx2/commit/de96d810ee4e309d118982fe7084a46a2bcd600d","name":"https://github.com/pydantic/httpx2/commit/de96d810ee4e309d118982fe7084a46a2bcd600d","tags":["x_refsource_MISC"]},{"url":"https://github.com/pydantic/httpx2/releases/tag/v2.11.0","name":"https://github.com/pydantic/httpx2/releases/tag/v2.11.0","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"NONE","baseScore":5.3,"baseSeverity":"MEDIUM","confidentialityImpact":"NONE","integrityImpact":"LOW","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-93","lang":"en","description":"CWE-93: Improper Neutralization of CRLF Sequences ('CRLF Injection')","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-09-02T17:57:17.092Z"},"source":{"advisory":"GHSA-h4x7-gw46-3wm6","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","references":[{"url":"https://github.com/pydantic/httpx2/security/advisories/GHSA-h4x7-gw46-3wm6","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-09-02T18:20:04.628894Z","id":"CVE-2026-84379","options":[{"Exploitation":"poc"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-09-02T18:20:46.599Z"}}]}}}