{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-45372", "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "state": "PUBLISHED", "assignerShortName": "GitHub_M", "dateReserved": "2026-05-12T00:51:29.086Z", "datePublished": "2026-05-29T19:21:12.313Z", "dateUpdated": "2026-05-29T19:21:12.313Z"}, "containers": {"cna": {"title": "cpp-httplib: HTTP header value percent-decoding in server-side `parse_header` enables CRLF injection", "problemTypes": [{"descriptions": [{"cweId": "CWE-93", "lang": "en", "description": "CWE-93: Improper Neutralization of CRLF Sequences ('CRLF Injection')", "type": "CWE"}]}, {"descriptions": [{"cweId": "CWE-444", "lang": "en", "description": "CWE-444: Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')", "type": "CWE"}]}], "metrics": [{"cvssV3_1": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "LOW", "baseScore": 9.9, "baseSeverity": "CRITICAL", "confidentialityImpact": "LOW", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "scope": "CHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:H/A:L", "version": "3.1"}}], "references": [{"name": "https://github.com/yhirose/cpp-httplib/security/advisories/GHSA-xjxg-64p4-vj4m", "tags": ["x_refsource_CONFIRM"], "url": "https://github.com/yhirose/cpp-httplib/security/advisories/GHSA-xjxg-64p4-vj4m"}], "affected": [{"vendor": "yhirose", "product": "cpp-httplib", "versions": [{"version": "< 0.44.0", "status": "affected"}]}], "providerMetadata": {"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "shortName": "GitHub_M", "dateUpdated": "2026-05-29T19:21:12.313Z"}, "descriptions": [{"lang": "en", "value": "cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to 0.44.0, when cpp-httplib's server parses an incoming request, it applies percent-decoding to every header value except Location and Referer. The validity check (is_field_value) is run before decoding, so encoded %0D%0A passes the check and is then expanded to a literal \\r\\n byte pair inside the stored header value. This vulnerability is fixed in 0.44.0."}], "source": {"advisory": "GHSA-xjxg-64p4-vj4m", "discovery": "UNKNOWN"}}}}

{}

{"cveTags": [], "descriptions": [{"lang": "en", "value": "cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to 0.44.0, when cpp-httplib's server parses an incoming request, it applies percent-decoding to every header value except Location and Referer. The validity check (is_field_value) is run before decoding, so encoded %0D%0A passes the check and is then expanded to a literal \\r\\n byte pair inside the stored header value. This vulnerability is fixed in 0.44.0."}], "id": "CVE-2026-45372", "lastModified": "2026-05-29T20:23:08.683", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "LOW", "baseScore": 9.9, "baseSeverity": "CRITICAL", "confidentialityImpact": "LOW", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "scope": "CHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:H/A:L", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 5.3, "source": "security-advisories@github.com", "type": "Secondary"}]}, "published": "2026-05-29T20:16:26.473", "references": [{"source": "security-advisories@github.com", "url": "https://github.com/yhirose/cpp-httplib/security/advisories/GHSA-xjxg-64p4-vj4m"}], "sourceIdentifier": "security-advisories@github.com", "vulnStatus": "Awaiting Analysis", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-93"}, {"lang": "en", "value": "CWE-444"}], "source": "security-advisories@github.com", "type": "Primary"}]}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0,0.44.0)"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "cpp-httplib", "source": "cna", "vendor": "yhirose"}, "product": "cpp-httplib", "vendor": "yhirose"}], "created": "2026-05-29T21:30:05.968658+00:00", "updated": "2026-05-29T21:30:06.279939+00:00", "vendors": ["yhirose", "yhirose$PRODUCT$cpp-httplib"]}