{"id":"CVE-2026-31478","summary":"ksmbd: replace hardcoded hdr2_len with offsetof() in smb2_calc_max_out_buf_len()","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: replace hardcoded hdr2_len with offsetof() in smb2_calc_max_out_buf_len()\n\nAfter this commit (e2b76ab8b5c9 \"ksmbd: add support for read compound\"),\nresponse buffer management was changed to use dynamic iov array.\nIn the new design, smb2_calc_max_out_buf_len() expects the second\nargument (hdr2_len) to be the offset of -\u003eBuffer field in the\nresponse structure, not a hardcoded magic number.\nFix the remaining call sites to use the correct offsetof() value.","modified":"2026-05-18T05:59:49.831427484Z","published":"2026-04-22T13:54:06.157Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/31xxx/CVE-2026-31478.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/0e55f63dd08f09651d39e1b709a91705a8a0ddcb"},{"type":"WEB","url":"https://git.kernel.org/stable/c/4cb537ae4f37d7d0f617815ed4bed7173fb50861"},{"type":"WEB","url":"https://git.kernel.org/stable/c/6aef1765d6807e0f027cd87f6ac973eb0879a46d"},{"type":"WEB","url":"https://git.kernel.org/stable/c/70b4c414889492c522b6e4331562360f49be2361"},{"type":"WEB","url":"https://git.kernel.org/stable/c/80824c7e527b70cf9039534e60aff592e8f209d1"},{"type":"WEB","url":"https://git.kernel.org/stable/c/9a7166f0ef8cbb7bb48dd05e2471d995566003f5"},{"type":"WEB","url":"https://git.kernel.org/stable/c/c3a89e3ec1ccf64fa6a34e391e1581ebbcba8683"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/31xxx/CVE-2026-31478.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-31478"},{"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":"f2283680a80571ca82d710bc6ecd8f8beac67d63"},{"fixed":"70b4c414889492c522b6e4331562360f49be2361"}]},{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"9f297df20d93411c0b4ddad7f88ba04a7cd36e77"},{"fixed":"9a7166f0ef8cbb7bb48dd05e2471d995566003f5"}]},{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"e2b76ab8b5c9327ab2dae6da05d0752eb2f4771d"},{"fixed":"c3a89e3ec1ccf64fa6a34e391e1581ebbcba8683"},{"fixed":"6aef1765d6807e0f027cd87f6ac973eb0879a46d"},{"fixed":"80824c7e527b70cf9039534e60aff592e8f209d1"},{"fixed":"4cb537ae4f37d7d0f617815ed4bed7173fb50861"},{"fixed":"0e55f63dd08f09651d39e1b709a91705a8a0ddcb"}]}],"versions":["v5.15.202","v5.15.201","v5.15.200","v5.15.199","v5.15.198","v5.15.197","v5.15.196","v5.15.195","v5.15.194","v5.15.193","v5.15.192","v5.15.191","v5.15.190","v5.15.189","v5.15.188","v5.15.187","v5.15.186","v5.15.185","v5.15.184","v5.15.183","v5.15.182","v5.15.181","v5.15.180","v5.15.179","v5.15.178","v5.15.177","v5.15.176","v5.15.175","v5.15.174","v5.15.173","v5.15.172","v5.15.171","v5.15.170","v5.15.169","v5.15.168","v5.15.167","v5.15.166","v5.15.165","v5.15.164","v5.15.163","v5.15.162","v5.15.161","v5.15.160","v5.15.159","v5.15.158","v5.15.157","v5.15.156","v5.15.155","v5.15.154","v5.15.153","v5.15.152","v5.15.151","v5.15.150","v5.15.149","v5.15.148","v5.15.147","v5.15.146","v5.15.145","v6.1.167","v6.1.166","v6.1.165","v6.1.164","v6.1.163","v6.1.162","v6.1.161","v6.1.160","v6.1.159","v6.1.158","v6.1.157","v6.1.156","v6.1.155","v6.1.154","v6.1.153","v6.1.152","v6.1.151","v6.1.150","v6.1.149","v6.1.148","v6.1.147","v6.1.146","v6.1.145","v6.1.144","v6.1.143","v6.1.142","v6.1.141","v6.1.140","v6.1.139","v6.1.138","v6.1.137","v6.1.136","v6.1.135","v6.1.134","v6.1.133","v6.1.132","v6.1.131","v6.1.130","v6.1.129","v6.1.128","v6.1.127","v6.1.126","v6.1.125","v6.1.124","v6.1.123","v6.1.122","v6.1.121","v6.1.120","v6.1.119","v6.1.118","v6.1.117","v6.1.116","v6.1.115","v6.1.114","v6.1.113","v6.1.112","v6.1.111","v6.1.110","v6.1.109","v6.1.108","v6.1.107","v6.1.106","v6.1.105","v6.1.104","v6.1.103","v6.1.102","v6.1.101","v6.1.100","v6.1.99","v6.1.98","v6.1.97","v6.1.96","v6.1.95","v6.1.94","v6.1.93","v6.1.92","v6.1.91","v6.1.90","v6.1.89","v6.1.88","v6.1.87","v6.1.86","v6.1.85","v6.1.84","v6.1.83","v6.1.82","v6.1.81","v6.1.80","v6.1.79","v6.1.78","v6.1.77","v6.1.76","v6.1.75","v6.1.74","v6.1.73","v6.1.72","v6.1.71"],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-31478.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"5.15.203"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.1.168"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.131"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.6.0"},{"fixed":"6.12.80"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.18.21"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.19.11"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-31478.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"}]}