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{"acknowledgement": "Red Hat would like to thank Etienne Champetier for reporting this issue.", "bugzilla": {"description": "kernel: layer 2 network filtering capabilities bypass / wifi", "id": "2010816", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2010816"}, "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 combinations of VLAN 0 headers, LLC/SNAP headers, and converting frames from Ethernet to Wifi and its reverse.", "Layer 2 network filtering capabilities such as IPv6 RA guard can be bypassed using combinations of VLAN 0 headers, LLC/SNAP headers and Ethernet to Wifi frame translation."], "name": "CVE-2021-27854", "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"}], "public_date": "2021-09-27T10:30:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2021-27854\nhttps://nvd.nist.gov/vuln/detail/CVE-2021-27854"], "statement": "Red Hat deems this to be a configuration issue. There is no vulnerability in the Linux kernel itself, there is a lot of ways to misuse the filtering facilities provided by the kernel and do insecure filtering rules, but you also have everything to actually set up secure rules.", "threat_severity": "Moderate"}