{"id":"CVE-2026-31428","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: nfnetlink_log: fix uninitialized padding leak in NFULA_PAYLOAD\n\n__build_packet_message() manually constructs the NFULA_PAYLOAD netlink\nattribute using skb_pu…","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: nfnetlink_log: fix uninitialized padding leak in NFULA_PAYLOAD\n\n__build_packet_message() manually constructs the NFULA_PAYLOAD netlink\nattribute using skb_pu…","severity":"medium","cvss":5.5,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","cwe":["CWE-908"],"vendor":"linux","product":"linux_kernel","affected":["linux_kernel >= 2.6.24, < 5.10.253","linux_kernel >= 5.11, < 5.15.203","linux_kernel >= 5.16, < 6.1.168","linux_kernel >= 6.2, < 6.6.131","linux_kernel >= 6.7, < 6.12.80","linux_kernel >= 6.13, < 6.18.21","linux_kernel >= 6.19, < 6.19.11","linux_kernel = 7.0"],"patched":["linux_kernel 6.19.11"],"published":"2026-04-13","updated":"2026-10-15","sourceUpdated":"2026-10-15T02:19:04.760","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-31428","references":[{"url":"https://git.kernel.org/stable/c/21d8efda029948d3666b0db5afcc0d36c0984aae","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/52025ebaa29f4eb4ed8bf92ce83a68f24ab7fdf7","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/7eff72968161fb8ddb26113344de3b92fb7d7ef5","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/7f3e5d72455936f42709116fabeca3bb216cda62","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/a2f6ff3444b663d6cfa63eadd61327a18592885a","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/a8365d1064ded323797c5e28e91070c52f44b76c","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/c9f6c51d36482805ac3ffadb9663fe775a13e926","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/fc961dd7272b5e4a462999635e44a4770d7f2482","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-019113.html","label":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-082556.html","label":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-457936.html","label":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"}],"tags":["nvd","cve.org"],"epss":0.00131,"epssPercentile":0.02657,"ingestedAt":"2026-09-08T15:33:26.990Z","slug":"CVE-2026-31428","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: nfnetlink_log: fix uninitialized padding leak in NFULA_PAYLOAD\n\n__build_packet_message() manually constructs the NFULA_PAYLOAD netlink\nattribute using skb_put() and skb_copy_bits(), bypassing the standard\nnla_reserve()/nla_put() helpers. While nla_total_size(data_len) bytes\nare allocated (including NLA alignment padding), only data_len bytes\nof actual packet data are copied. The trailing nla_padlen(data_len)\nbytes (1-3 when data_len is not 4-byte aligned) are never initialized,\nleaking stale heap contents to userspace via the NFLOG netlink socket.\n\nReplace the manual attribute construction with nla_reserve(), which\nhandles the tailroom check, header setup, and padding zeroing via\n__nla_reserve(). The subsequent skb_copy_bits() fills in the payload\ndata on top of the properly initialized attribute.\n\n## Affected\n\n- `linux_kernel >= 2.6.24, < 5.10.253`\n- `linux_kernel >= 5.11, < 5.15.203`\n- `linux_kernel >= 5.16, < 6.1.168`\n- `linux_kernel >= 6.2, < 6.6.131`\n- `linux_kernel >= 6.7, < 6.12.80`\n- `linux_kernel >= 6.13, < 6.18.21`\n- `linux_kernel >= 6.19, < 6.19.11`\n- `linux_kernel = 7.0`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `linux_kernel 6.19.11`","depth":"sunlit","depthScore":30,"depthScoreParts":{"impact":30.3,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[{"seq":221707,"id":"CVE-2026-31428","ts":1792035330852,"field":"cvss","old":null,"new":"5.5"},{"seq":221706,"id":"CVE-2026-31428","ts":1792035330852,"field":"severity","old":"none","new":"medium"}]}