{"cve":"CVE-2026-74579","nvd":{"published":"2026-08-17T06:19:56.417","modified":"2026-10-16T20:17:39.580","status":"Received","description":"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 << 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.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H","score":7.1},"cwes":[],"references":["https://git.kernel.org/stable/c/16b553c46e347bc9de9946c4960654d5884a86de","https://git.kernel.org/stable/c/363c3a84a946d53e5e121c9f47c7c2b7d228c46b","https://git.kernel.org/stable/c/39e88f28fb32bf02bd4b525c24c842c9cff5663d","https://git.kernel.org/stable/c/3ee7b3f813b11f28cd6efdf7f24d64b5a7fd4dc7","https://git.kernel.org/stable/c/630295d5bba1d0e0f494cc459452eb0a0058c545"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:49:10.689564601+00:00"},"epss":{"cve":"CVE-2026-74579","score":0.0012,"percentile":0.01828,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}