{"dataType": "CVE_RECORD", "dataVersion": "5.1", "cveMetadata": {"state": "PUBLISHED", "cveId": "CVE-2021-27861", "assignerOrgId": "37e5125f-f79b-445b-8fad-9564f167944b", "assignerShortName": "certcc", "datePublished": "2022-09-27T18:40:13.742316Z", "dateUpdated": "2024-09-16T16:47:46.467Z", "dateReserved": "2021-03-01T00:00:00"}, "containers": {"cna": {"title": "L2 network filtering bypass using stacked VLAN0 and LLC/SNAP headers with invalid lengths", "datePublic": "2022-09-27T00:00:00", "providerMetadata": {"orgId": "37e5125f-f79b-445b-8fad-9564f167944b", "shortName": "certcc", "dateUpdated": "2022-10-12T00:00:00"}, "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 optionally VLAN0 headers)"}], "affected": [{"vendor": "IEEE", "product": "802.2", "versions": [{"version": "802.2h-1997", "status": "affected", "lessThanOrEqual": "802.2h-1997", "versionType": "custom"}]}, {"vendor": "IETF", "product": "draft-ietf-v6ops-ra-guard", "versions": [{"version": "08", "status": "affected", "lessThanOrEqual": "08", "versionType": "custom"}]}, {"vendor": "IETF", "product": "P802.1Q", "versions": [{"version": "D1.0", "status": "affected", "lessThanOrEqual": "D1.0", "versionType": "custom"}]}], "references": [{"url": "https://datatracker.ietf.org/doc/draft-ietf-v6ops-ra-guard/08/"}, {"url": "https://standards.ieee.org/ieee/802.2/1048/"}, {"url": "https://standards.ieee.org/ieee/802.1Q/10323/"}, {"url": "https://kb.cert.org/vuls/id/855201"}, {"url": "https://blog.champtar.fr/VLAN0_LLC_SNAP/"}], "credits": [{"lang": "en", "value": "Etienne Champetier (@champtar) <champetier.etienne@gmail.com>"}], "problemTypes": [{"descriptions": [{"type": "CWE", "lang": "en", "description": "CWE-130 Improper Handling of Length Parameter", "cweId": "CWE-130"}]}, {"descriptions": [{"type": "CWE", "lang": "en", "description": "CWE-290: Authentication Bypass by Spoofing", "cweId": "CWE-290"}]}], "source": {"discovery": "EXTERNAL"}}, "adp": [{"providerMetadata": {"orgId": "af854a3a-2127-422b-91ae-364da2661108", "shortName": "CVE", "dateUpdated": "2024-08-03T21:33:17.074Z"}, "title": "CVE Program Container", "references": [{"url": "https://datatracker.ietf.org/doc/draft-ietf-v6ops-ra-guard/08/", "tags": ["x_transferred"]}, {"url": "https://standards.ieee.org/ieee/802.2/1048/", "tags": ["x_transferred"]}, {"url": "https://standards.ieee.org/ieee/802.1Q/10323/", "tags": ["x_transferred"]}, {"url": "https://kb.cert.org/vuls/id/855201", "tags": ["x_transferred"]}, {"url": "https://blog.champtar.fr/VLAN0_LLC_SNAP/", "tags": ["x_transferred"]}]}]}}

{}

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{"bugzilla": {"description": "Kernel: Layer 2 network filtering capabilities bypass with invalid length (and optionally VLAN0 headers)", "id": "2130301", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2130301"}, "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 optionally VLAN0 headers)", "Layer 2 network filtering capabilities such as IPv6 RA guard can be bypassed using LLC/SNAP headers with invalid length (and optionally VLAN0 headers)"], "name": "CVE-2021-27861", "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": "2022-09-27T10:30:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2021-27861\nhttps://nvd.nist.gov/vuln/detail/CVE-2021-27861\nhttps://www.cisco.com/c/en/us/support/docs/csa/cisco-sa-VU855201-J3z8CKTX.html"], "threat_severity": "Moderate"}