{ "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" } } ] } }