{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-21428","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","state":"PUBLISHED","assignerShortName":"GitHub_M","dateReserved":"2025-12-29T03:00:29.274Z","datePublished":"2026-01-01T17:54:43.959Z","dateUpdated":"2026-01-02T18:50:20.380Z"},"containers":{"cna":{"title":"cpp-httplib has CRLF injection in http headers","problemTypes":[{"descriptions":[{"cweId":"CWE-93","lang":"en","description":"CWE-93: Improper Neutralization of CRLF Sequences ('CRLF Injection')","type":"CWE"}]}],"metrics":[{"cvssV4_0":{"attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"NONE","privilegesRequired":"NONE","userInteraction":"NONE","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"HIGH","vulnAvailabilityImpact":"NONE","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","subAvailabilityImpact":"NONE","baseScore":7.7,"baseSeverity":"HIGH","vectorString":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:P","version":"4.0"}}],"references":[{"name":"https://github.com/yhirose/cpp-httplib/security/advisories/GHSA-wpc6-j37r-jcx7","tags":["x_refsource_CONFIRM"],"url":"https://github.com/yhirose/cpp-httplib/security/advisories/GHSA-wpc6-j37r-jcx7"},{"name":"https://github.com/yhirose/cpp-httplib/commit/98048a033a532ff22320ce1d11789f8d5710dfcd","tags":["x_refsource_MISC"],"url":"https://github.com/yhirose/cpp-httplib/commit/98048a033a532ff22320ce1d11789f8d5710dfcd"},{"name":"https://github.com/yhirose/cpp-httplib/releases/tag/v0.30.0","tags":["x_refsource_MISC"],"url":"https://github.com/yhirose/cpp-httplib/releases/tag/v0.30.0"}],"affected":[{"vendor":"yhirose","product":"cpp-httplib","versions":[{"version":"< 0.30.0","status":"affected"}]}],"providerMetadata":{"orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","shortName":"GitHub_M","dateUpdated":"2026-01-01T17:54:43.959Z"},"descriptions":[{"lang":"en","value":"cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to version 0.30.0, the ``write_headers`` function does not check for CR & LF characters in user supplied headers, allowing untrusted header value to escape header lines.\nThis vulnerability allows attackers to add extra headers, modify request body unexpectedly & trigger an SSRF attack. When combined with a server that supports http1.1 pipelining (springboot, python twisted etc), this can be used for server side request forgery (SSRF). Version 0.30.0 fixes this issue."}],"source":{"advisory":"GHSA-wpc6-j37r-jcx7","discovery":"UNKNOWN"}},"adp":[{"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-01-02T18:50:07.704892Z","id":"CVE-2026-21428","options":[{"Exploitation":"poc"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"title":"CISA ADP Vulnrichment","providerMetadata":{"orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP","dateUpdated":"2026-01-02T18:50:20.380Z"}}]}}