{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-112112", "assignerOrgId": "8254265b-2729-46b6-b9e3-3dfca2d5bfca", "state": "PUBLISHED", "assignerShortName": "mitre", "dateReserved": "2026-10-18T23:01:05.103Z", "datePublished": "2026-10-18T23:01:05.633Z", "dateUpdated": "2026-10-18T23:01:05.633Z"}, "containers": {"cna": {"affected": [{"defaultStatus": "unknown", "modules": ["IPv6 FlowSpec validation"], "product": "BIRD", "programFiles": ["nest/rt-table.c"], "programRoutines": [{"name": "net_flow_has_dst_prefix"}], "repo": "https://gitlab.nic.cz/labs/bird", "vendor": "nic", "versions": [{"lessThanOrEqual": "2.20.0", "status": "affected", "version": "2.0.9", "versionType": "semver"}, {"lessThanOrEqual": "3.4.0", "status": "affected", "version": "3.0.0", "versionType": "semver"}]}], "configurations": [{"lang": "en", "supportingMedia": [{"base64": false, "type": "text/html", "value": "<p>An established BGP peer must be able to send IPv6 FlowSpec to a receiving flow6 channel configured with \"validate yes\". A suitable unicast route from that peer must be present in the base table. Propagation additionally requires an export policy permitting the rule. Data-plane impact depends on downstream support for, acceptance of, and enforcement of the FlowSpec match and action.</p>"}], "value": "An established BGP peer must be able to send IPv6 FlowSpec to a receiving flow6 channel configured with \"validate yes\". A suitable unicast route from that peer must be present in the base table. Propagation additionally requires an export policy permitting the rule. Data-plane impact depends on downstream support for, acceptance of, and enforcement of the FlowSpec match and action."}], "descriptions": [{"lang": "en", "value": "An IPv6 FlowSpec validation bypass in the CZ.NIC BIRD Internet Routing Daemon allows an established BGP peer to inject FlowSpec rules matching destinations outside the address space authorized by the unicast-route validation procedure. With validation enabled on the receiving flow6 channel, BIRD fails to reject a destination prefix component with a nonzero offset, contrary to RFC 8956 section 5. It validates a reconstructed prefix with zero-filled skipped bits, although the original FlowSpec component can match a broader set of IPv6 addresses. Given a suitable unicast route from the peer, the rule can pass validation and, where export policy permits, be propagated to downstream peers. Downstream enforcement may cause unauthorized traffic filtering or redirection."}], "metrics": [{"cvssV4_0": {"Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "Safety": "NOT_DEFINED", "attackComplexity": "LOW", "attackRequirements": "PRESENT", "attackVector": "NETWORK", "baseScore": 2.3, "baseSeverity": "LOW", "privilegesRequired": "LOW", "providerUrgency": "NOT_DEFINED", "subAvailabilityImpact": "NONE", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "userInteraction": "NONE", "valueDensity": "NOT_DEFINED", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N", "version": "4.0", "vulnAvailabilityImpact": "NONE", "vulnConfidentialityImpact": "NONE", "vulnIntegrityImpact": "LOW", "vulnerabilityResponseEffort": "NOT_DEFINED"}, "format": "CVSS", "scenarios": [{"lang": "en", "value": "GENERAL"}]}], "problemTypes": [{"descriptions": [{"cweId": "CWE-1284", "description": "CWE-1284 Improper Validation of Specified Quantity in Input", "lang": "en", "type": "CWE"}]}], "providerMetadata": {"orgId": "8254265b-2729-46b6-b9e3-3dfca2d5bfca", "shortName": "mitre", "dateUpdated": "2026-10-18T23:01:05.633Z"}, "references": [{"tags": ["patch"], "url": "https://gitlab.nic.cz/labs/bird/-/commit/7cf75587b6f38b87849fe192bf5dfd124b7702bc"}, {"url": "https://www.rfc-editor.org/rfc/rfc8956.html#section-5"}, {"url": "https://gitlab.nic.cz/labs/bird/-/blob/v2.20.0/nest/rt-table.c#L2686"}, {"url": "https://gitlab.nic.cz/labs/bird/-/blob/v3.4.0/nest/rt-table.c#L4518"}], "solutions": [{"lang": "en", "supportingMedia": [{"base64": false, "type": "text/html", "value": "<p>Apply upstream commit 7cf75587b6f38b87849fe192bf5dfd124b7702bc or a verified branch-specific backport. The fix requires the original IPv6 destination-prefix component to have offset zero before it can pass FlowSpec validation. The first fixed release has not yet been verified.</p>"}], "value": "Apply upstream commit 7cf75587b6f38b87849fe192bf5dfd124b7702bc or a verified branch-specific backport. The fix requires the original IPv6 destination-prefix component to have offset zero before it can pass FlowSpec validation. The first fixed release has not yet been verified."}], "x_generator": {"engine": "CVE-Request-form 0.0.1"}, "cpeApplicability": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:nic:bird:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.0.9", "versionEndIncluding": "2.20.0"}, {"vulnerable": true, "criteria": "cpe:2.3:a:nic:bird:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.0.0", "versionEndIncluding": "3.4.0"}]}]}]}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unknown", "modules": ["IPv6 FlowSpec validation"], "product": "BIRD", "programFiles": ["nest/rt-table.c"], "programRoutines": [{"name": "net_flow_has_dst_prefix"}], "repo": "https://gitlab.nic.cz/labs/bird", "vendor": "nic", "versions": [{"lessThanOrEqual": "2.20.0", "status": "affected", "version": "2.0.9", "versionType": "semver"}, {"lessThanOrEqual": "3.4.0", "status": "affected", "version": "3.0.0", "versionType": "semver"}]}], "source": "cve@mitre.org"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "An IPv6 FlowSpec validation bypass in the CZ.NIC BIRD Internet Routing Daemon allows an established BGP peer to inject FlowSpec rules matching destinations outside the address space authorized by the unicast-route validation procedure. With validation enabled on the receiving flow6 channel, BIRD fails to reject a destination prefix component with a nonzero offset, contrary to RFC 8956 section 5. It validates a reconstructed prefix with zero-filled skipped bits, although the original FlowSpec component can match a broader set of IPv6 addresses. Given a suitable unicast route from the peer, the rule can pass validation and, where export policy permits, be propagated to downstream peers. Downstream enforcement may cause unauthorized traffic filtering or redirection."}], "id": "CVE-2026-112112", "lastModified": "2026-10-18T23:16:56.767", "metrics": {"cvssMetricV40": [{"cvssData": {"Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "Safety": "NOT_DEFINED", "attackComplexity": "LOW", "attackRequirements": "PRESENT", "attackVector": "NETWORK", "availabilityRequirement": "NOT_DEFINED", "baseScore": 2.3, "baseSeverity": "LOW", "confidentialityRequirement": "NOT_DEFINED", "exploitMaturity": "NOT_DEFINED", "integrityRequirement": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "privilegesRequired": "LOW", "providerUrgency": "NOT_DEFINED", "subAvailabilityImpact": "NONE", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "userInteraction": "NONE", "valueDensity": "NOT_DEFINED", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X", "version": "4.0", "vulnAvailabilityImpact": "NONE", "vulnConfidentialityImpact": "NONE", "vulnIntegrityImpact": "LOW", "vulnerabilityResponseEffort": "NOT_DEFINED"}, "source": "cve@mitre.org", "type": "Secondary"}]}, "published": "2026-10-18T23:16:56.767", "references": [{"source": "cve@mitre.org", "url": "https://gitlab.nic.cz/labs/bird/-/blob/v2.20.0/nest/rt-table.c#L2686"}, {"source": "cve@mitre.org", "url": "https://gitlab.nic.cz/labs/bird/-/blob/v3.4.0/nest/rt-table.c#L4518"}, {"source": "cve@mitre.org", "url": "https://gitlab.nic.cz/labs/bird/-/commit/7cf75587b6f38b87849fe192bf5dfd124b7702bc"}, {"source": "cve@mitre.org", "url": "https://www.rfc-editor.org/rfc/rfc8956.html#section-5"}], "sourceIdentifier": "cve@mitre.org", "vulnStatus": "Received", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-1284"}], "source": "cve@mitre.org", "type": "Primary"}]}

{}

{"created": "2026-10-19T00:30:06.389175+00:00", "title": "IPv6 FlowSpec Validation Bypass in BIRD Daemon", "updated": "2026-10-19T00:30:06.389181+00:00", "vendors": []}