{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-42533", "assignerOrgId": "9dacffd4-cb11-413f-8451-fbbfd4ddc0ab", "state": "PUBLISHED", "assignerShortName": "f5", "dateReserved": "2026-05-05T21:19:09.517Z", "datePublished": "2026-07-15T14:33:45.810Z", "dateUpdated": "2026-07-15T21:20:26.156Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "9dacffd4-cb11-413f-8451-fbbfd4ddc0ab", "shortName": "f5", "dateUpdated": "2026-07-15T21:20:26.156Z"}, "title": "NGINX Map directive and Regex matching vulnerability", "datePublic": "2026-07-15T14:00:00.000Z", "problemTypes": [{"descriptions": [{"lang": "en", "cweId": "CWE-122", "description": "CWE-122 Heap-based Buffer Overflow", "type": "CWE"}]}], "affected": [{"vendor": "F5", "product": "NGINX Plus", "modules": ["map directive with regex matching"], "versions": [{"status": "affected", "version": "37.0.0.1", "lessThan": "37.0.3.1", "versionType": "custom"}, {"status": "affected", "version": "R36", "lessThan": "R36 P7", "versionType": "custom"}, {"status": "affected", "version": "R33", "lessThan": "*", "versionType": "custom"}], "defaultStatus": "unknown"}, {"vendor": "F5", "product": "NGINX Open Source", "modules": ["map directive with regex matching"], "versions": [{"status": "affected", "version": "1.31.2", "lessThan": "1.31.3", "versionType": "custom"}, {"status": "affected", "version": "0.9.6", "lessThan": "1.30.4", "versionType": "custom"}], "defaultStatus": "unknown"}], "descriptions": [{"lang": "en", "value": "A vulnerability exists in NGINX Plus and NGINX Open Source when a map\u00a0directive uses regex matching and a string expression references the map's regex capture variables before referencing the map output variable. 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