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{"bugzilla": {"description": "kernel: netfilter: nf_tables: unlink table before deleting it", "id": "2282344", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2282344"}, "csaw": false, "cvss3": {"cvss3_base_score": "7.1", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H", "status": "draft"}, "cwe": "CWE-416", "details": ["In the Linux kernel, the following vulnerability has been resolved:\nnetfilter: nf_tables: unlink table before deleting it\nsyzbot reports following UAF:\nBUG: KASAN: use-after-free in memcmp+0x18f/0x1c0 lib/string.c:955\nnla_strcmp+0xf2/0x130 lib/nlattr.c:836\nnft_table_lookup.part.0+0x1a2/0x460 net/netfilter/nf_tables_api.c:570\nnft_table_lookup net/netfilter/nf_tables_api.c:4064 [inline]\nnf_tables_getset+0x1b3/0x860 net/netfilter/nf_tables_api.c:4064\nnfnetlink_rcv_msg+0x659/0x13f0 net/netfilter/nfnetlink.c:285\nnetlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2504\nProblem is that all get operations are lockless, so the commit_mutex\nheld by nft_rcv_nl_event() isn't enough to stop a parallel GET request\nfrom doing read-accesses to the table object even after synchronize_rcu().\nTo avoid this, unlink the table first and store the table objects in\non-stack scratch space."], "name": "CVE-2021-47394", "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": "Out of support scope", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Out of support scope", "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": "2024-05-21T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2021-47394\nhttps://nvd.nist.gov/vuln/detail/CVE-2021-47394\nhttps://lore.kernel.org/linux-cve-announce/2024052147-CVE-2021-47394-9ec5@gregkh/T"], "threat_severity": "Moderate"}

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