{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-88831", "assignerOrgId": "53f830b8-0a3f-465b-8143-3b8a9948e749", "state": "PUBLISHED", "assignerShortName": "redhat", "dateReserved": "2026-09-10T09:42:04.559Z", "datePublished": "2026-09-23T17:45:23.299Z", "dateUpdated": "2026-09-23T18:11:48.288Z"}, "containers": {"cna": {"title": "Busybox: busybox: httpd silently fails open when ip deny rules contain invalid cidr prefix lengths", "metrics": [{"other": {"content": {"value": "Moderate", "namespace": "https://access.redhat.com/security/updates/classification/"}, "type": "Red Hat severity rating"}}, {"cvssV3_1": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 5.3, "baseSeverity": "MEDIUM", "confidentialityImpact": "LOW", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N", "version": "3.1"}, "format": "CVSS"}], "descriptions": [{"lang": "en", "value": "BusyBox httpd IP deny rules with invalid CIDR prefix lengths fail open, leaving a parsed IP with a zeroed mask so the rule matches no clients."}], "affected": [{"vendor": "Red Hat", "product": "Red Hat Hardened Images", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "packageName": "busybox", "defaultStatus": "affected", "cpes": ["cpe:/a:redhat:hummingbird:1"]}], "references": [{"url": "https://access.redhat.com/security/cve/CVE-2026-88831", "tags": ["vdb-entry", "x_refsource_REDHAT"]}, {"url": "https://bugzilla.redhat.com/show_bug.cgi?id=2531346", "name": "RHBZ#2531346", "tags": ["issue-tracking", "x_refsource_REDHAT"]}], "datePublic": "2026-09-23T16:35:00.000Z", "problemTypes": [{"descriptions": [{"cweId": "CWE-636", "description": "Not Failing Securely ('Failing Open')", "lang": "en", "type": "CWE"}]}], "x_redhatCweChain": "CWE-636: Not Failing Securely ('Failing Open')", "workarounds": [{"lang": "en", "value": "Audit all BusyBox httpd configuration files for syntactically valid CIDR prefix lengths. Implement network-level access controls (iptables/nftables) as the primary enforcement layer rather than relying on application-level ACLs."}], "timeline": [{"lang": "en", "time": "2026-09-09T00:00:00.000Z", "value": "Reported to Red Hat."}, {"lang": "en", "time": "2026-09-23T16:35:00.000Z", "value": "Made public."}], "providerMetadata": {"orgId": "53f830b8-0a3f-465b-8143-3b8a9948e749", "shortName": "redhat", "dateUpdated": "2026-09-23T17:45:23.299Z"}, "x_generator": {"engine": "cvelib 1.8.0"}}, "adp": [{"metrics": [{"other": {"type": "ssvc", "content": {"timestamp": "2026-09-23T18:08:33.797869Z", "id": "CVE-2026-88831", "options": [{"Exploitation": "none"}, {"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": "2026-09-23T18:11:48.288Z"}}]}}

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-88831", "assignerOrgId": "53f830b8-0a3f-465b-8143-3b8a9948e749", "state": "PUBLISHED", "assignerShortName": "redhat", "dateReserved": "2026-09-10T09:42:04.559Z", "datePublished": "2026-09-23T17:45:23.299Z", "dateUpdated": "2026-09-23T18:11:48.288Z"}, "containers": {"cna": {"title": "Busybox: busybox: httpd silently fails open when ip deny rules contain invalid cidr prefix lengths", "metrics": [{"other": {"content": {"value": "Moderate", "namespace": "https://access.redhat.com/security/updates/classification/"}, "type": "Red Hat severity rating"}}, {"cvssV3_1": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 5.3, "baseSeverity": "MEDIUM", "confidentialityImpact": "LOW", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N", "version": "3.1"}, "format": "CVSS"}], "descriptions": [{"lang": "en", "value": "BusyBox httpd IP deny rules with invalid CIDR prefix lengths fail open, leaving a parsed IP with a zeroed mask so the rule matches no clients."}], "affected": [{"vendor": "Red Hat", "product": "Red Hat Hardened Images", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "packageName": "busybox", "defaultStatus": "affected", "cpes": ["cpe:/a:redhat:hummingbird:1"]}], "references": [{"url": "https://access.redhat.com/security/cve/CVE-2026-88831", "tags": ["vdb-entry", "x_refsource_REDHAT"]}, {"url": "https://bugzilla.redhat.com/show_bug.cgi?id=2531346", "name": "RHBZ#2531346", "tags": ["issue-tracking", "x_refsource_REDHAT"]}], "datePublic": "2026-09-23T16:35:00.000Z", "problemTypes": [{"descriptions": [{"cweId": "CWE-636", "description": "Not Failing Securely ('Failing Open')", "lang": "en", "type": "CWE"}]}], "x_redhatCweChain": "CWE-636: Not Failing Securely ('Failing Open')", "workarounds": [{"lang": "en", "value": "Audit all BusyBox httpd configuration files for syntactically valid CIDR prefix lengths. Implement network-level access controls (iptables/nftables) as the primary enforcement layer rather than relying on application-level ACLs."}], "timeline": [{"lang": "en", "time": "2026-09-09T00:00:00.000Z", "value": "Reported to Red Hat."}, {"lang": "en", "time": "2026-09-23T16:35:00.000Z", "value": "Made public."}], "providerMetadata": {"orgId": "53f830b8-0a3f-465b-8143-3b8a9948e749", "shortName": "redhat", "dateUpdated": "2026-09-23T17:45:23.299Z"}, "x_generator": {"engine": "cvelib 1.8.0"}}, "adp": [{"title": "CISA ADP Vulnrichment", "metrics": [{"other": {"type": "ssvc", "content": {"id": "CVE-2026-88831", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "yes"}, {"Technical Impact": "partial"}], "version": "2.0.3", "timestamp": "2026-09-23T18:08:33.797869Z"}}}], "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-09-23T18:10:58.581Z"}}]}}

{"affected": [{"affectedData": [{"collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "cpes": ["cpe:/a:redhat:hummingbird:1"], "defaultStatus": "affected", "packageName": "busybox", "product": "Red Hat Hardened Images", "vendor": "Red Hat"}], "source": "secalert@redhat.com"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "BusyBox httpd IP deny rules with invalid CIDR prefix lengths fail open, leaving a parsed IP with a zeroed mask so the rule matches no clients."}], "id": "CVE-2026-88831", "lastModified": "2026-09-23T19:19:42.490", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 5.3, "baseSeverity": "MEDIUM", "confidentialityImpact": "LOW", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 1.4, "source": "secalert@redhat.com", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-88831", "options": [{"exploitation": "none"}, {"automatable": "yes"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2026-09-23T18:08:33.797869Z", "version": "2.0.3"}}]}, "published": "2026-09-23T18:17:10.080", "references": [{"source": "secalert@redhat.com", "url": "https://access.redhat.com/security/cve/CVE-2026-88831"}, {"source": "secalert@redhat.com", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2531346"}], "sourceIdentifier": "secalert@redhat.com", "vulnStatus": "Received", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-636"}], "source": "secalert@redhat.com", "type": "Secondary"}]}

{}

{"created": "2026-09-23T20:00:09.002305+00:00", "updated": "2026-09-23T20:00:09.002310+00:00", "vendors": []}