CVE-2021-27862

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{"affected": [{"affectedData": [{"product": "802.2", "vendor": "IEEE", "versions": [{"lessThanOrEqual": "802.2h-1997", "status": "affected", "version": "802.2h-1997", "versionType": "custom"}]}, {"product": "draft-ietf-v6ops-ra-guard-08", "vendor": "IETF", "versions": [{"lessThanOrEqual": "08", "status": "affected", "version": "08", "versionType": "custom"}]}], "source": "cret@cert.org"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:a:ieee:ieee_802.2:*:*:*:*:*:*:*:*", "matchCriteriaId": "D5B0DDC2-21C5-4682-9AA2-055BF7C722DA", "versionEndIncluding": "802.2h-1997", "vulnerable": true}], "negate": false, "operator": "OR"}]}, {"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:a:ietf:p802.1q:*:*:*:*:*:*:*:*", "matchCriteriaId": "94105D2E-950F-4290-8840-301FA908BC8C", "versionEndIncluding": "d1.0", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "Layer 2 network filtering capabilities such as IPv6 RA guard can be bypassed using LLC/SNAP headers with invalid length and Ethernet to Wifi frame conversion (and optionally VLAN0 headers)."}, {"lang": "es", "value": "Las capacidades de filtrado de red de capa 2, como la protecci\u00f3n RA de IPv6, pueden omitirse usando encabezados LLC/SNAP con una longitud no v\u00e1lida y la conversi\u00f3n de tramas de Ethernet a Wifi (y, opcionalmente, encabezados VLAN0)"}], "id": "CVE-2021-27862", "lastModified": "2026-06-17T03:45:32.623", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "ADJACENT_NETWORK", "availabilityImpact": "NONE", "baseScore": 4.7, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "LOW", "privilegesRequired": "NONE", "scope": "CHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N", "version": "3.1"}, "exploitabilityScore": 2.8, "impactScore": 1.4, "source": "nvd@nist.gov", "type": "Primary"}, {"cvssData": {"attackComplexity": "LOW", "attackVector": "ADJACENT_NETWORK", "availabilityImpact": "NONE", "baseScore": 4.7, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "LOW", "privilegesRequired": "NONE", "scope": "CHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N", "version": "3.1"}, "exploitabilityScore": 2.8, "impactScore": 1.4, "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2021-27862", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2025-05-21T15:04:33.466068Z", "version": "2.0.3"}}]}, "published": "2022-09-27T19:15:09.403", "references": [{"source": "cret@cert.org", "url": "https://blog.champtar.fr/VLAN0_LLC_SNAP/"}, {"source": "cret@cert.org", "tags": ["Vendor Advisory"], "url": "https://datatracker.ietf.org/doc/draft-ietf-v6ops-ra-guard/08/"}, {"source": "cret@cert.org", "url": "https://kb.cert.org/vuls/id/855201"}, {"source": "cret@cert.org", "tags": ["Vendor Advisory"], "url": "https://standards.ieee.org/ieee/802.2/1048/"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "url": "https://blog.champtar.fr/VLAN0_LLC_SNAP/"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Vendor Advisory"], "url": "https://datatracker.ietf.org/doc/draft-ietf-v6ops-ra-guard/08/"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "url": "https://kb.cert.org/vuls/id/855201"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Vendor Advisory"], "url": "https://standards.ieee.org/ieee/802.2/1048/"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "url": "https://www.kb.cert.org/vuls/id/855201"}], "sourceIdentifier": "cret@cert.org", "vulnStatus": "Modified", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-130"}, {"lang": "en", "value": "CWE-290"}], "source": "cret@cert.org", "type": "Secondary"}, {"description": [{"lang": "en", "value": "CWE-290"}], "source": "nvd@nist.gov", "type": "Primary"}]}

{"bugzilla": {"description": "Kernel: Layer 2 network filtering capabilities bypass Wifi frame conversion (and optionally VLAN0 headers)", "id": "2130298", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2130298"}, "csaw": false, "cvss3": {"cvss3_base_score": "5.3", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N", "status": "draft"}, "details": ["Layer 2 network filtering capabilities such as IPv6 RA guard can be bypassed using LLC/SNAP headers with invalid length and Ethernet to Wifi frame conversion (and optionally VLAN0 headers).", "Layer 2 network filtering capabilities such as IPv6 RA guard can be bypassed using LLC/SNAP headers with invalid length and Ethernet to Wifi frame conversion (and optionally VLAN0 headers)."], "name": "CVE-2021-27862", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2022-09-29T12:30:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2021-27862\nhttps://nvd.nist.gov/vuln/detail/CVE-2021-27862"], "threat_severity": "Moderate"}

{}