{"id":"CVE-2026-74579","summary":"netfilter: nft_payload: fix mask build for partial field offload","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: nft_payload: fix mask build for partial field offload\n\nnft_payload_offload_mask() builds the offload match mask for a payload\nexpression that covers only part of a header field.  For a partial IPv6\naddress match (field_len = 16, priv_len = 1) that shift is 1 \u003c\u003c 120, which\nis undefined on the 32-bit int operand.  It also trims only one word, so\nthe remaining words stay 0xffffffff (and when priv_len is a multiple of 4\nthe trim is skipped entirely), leaving the mask covering more bytes than\nthe rule matches.\n\n  UBSAN: shift-out-of-bounds in net/netfilter/nft_payload.c:278:20\n  shift exponent 120 is too large for 32-bit type 'int'\n  ...\n\nThe match is byte-granular and struct nft_data is zero-initialised, so the\ncorrect mask is simply the first priv_len bytes set to 0xff. Set those\nbytes directly and drop the word/shift trimming; this removes the undefined\nshift and no longer over-masks the trailing bytes.","modified":"2026-10-28T02:31:03.069378877Z","published":"2026-08-17T05:28:27.768Z","related":["SUSE-SU-2026:24179-1","SUSE-SU-2026:24181-1","SUSE-SU-2026:24182-1","SUSE-SU-2026:24184-1","SUSE-SU-2026:24197-1","SUSE-SU-2026:24235-1","SUSE-SU-2026:24315-1","SUSE-SU-2026:24316-1","SUSE-SU-2026:4640-1","SUSE-SU-2026:4706-1","openSUSE-SU-2026:22091-1"],"database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/74xxx/CVE-2026-74579.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/16b553c46e347bc9de9946c4960654d5884a86de"},{"type":"WEB","url":"https://git.kernel.org/stable/c/363c3a84a946d53e5e121c9f47c7c2b7d228c46b"},{"type":"WEB","url":"https://git.kernel.org/stable/c/39e88f28fb32bf02bd4b525c24c842c9cff5663d"},{"type":"WEB","url":"https://git.kernel.org/stable/c/3ee7b3f813b11f28cd6efdf7f24d64b5a7fd4dc7"},{"type":"WEB","url":"https://git.kernel.org/stable/c/630295d5bba1d0e0f494cc459452eb0a0058c545"},{"type":"WEB","url":"https://git.kernel.org/stable/c/8720df4504e0ed1781a702f65251bd47b3534d5e"},{"type":"WEB","url":"https://git.kernel.org/stable/c/a375d8ace807767f29f276b681b6324c74929b1d"},{"type":"WEB","url":"https://git.kernel.org/stable/c/b19b5d2e042c294e2cc1c908dc598f9d64015396"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/74xxx/CVE-2026-74579.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-74579"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"a5d45bc0dc50f9dd83703510e9804d813a9cac32"},{"fixed":"3ee7b3f813b11f28cd6efdf7f24d64b5a7fd4dc7"},{"fixed":"8720df4504e0ed1781a702f65251bd47b3534d5e"},{"fixed":"363c3a84a946d53e5e121c9f47c7c2b7d228c46b"},{"fixed":"b19b5d2e042c294e2cc1c908dc598f9d64015396"},{"fixed":"a375d8ace807767f29f276b681b6324c74929b1d"},{"fixed":"16b553c46e347bc9de9946c4960654d5884a86de"},{"fixed":"630295d5bba1d0e0f494cc459452eb0a0058c545"},{"fixed":"39e88f28fb32bf02bd4b525c24c842c9cff5663d"}]},{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"5.9.14"},{"fixed":"5.10"}]},{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"5c2b4b4f9fa5b765b927e361e3d310bcb5773015"}]}],"versions":["v5.9.16","v5.9.15","v5.9.14"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-74579.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"5.10.0"},{"fixed":"5.10.265"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.11.0"},{"fixed":"5.15.216"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.1.183"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.151"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.103"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.44"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.1.8"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-74579.json"}}],"schema_version":"1.9.2","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H"}]}