{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-31704","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2026-03-09T15:48:24.132Z","datePublished":"2026-05-01T13:56:03.243Z","dateUpdated":"2026-05-11T22:14:08.692Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-05-11T22:14:08.692Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: use check_add_overflow() to prevent u16 DACL size overflow\n\nset_posix_acl_entries_dacl() and set_ntacl_dacl() accumulate ACE sizes\nin u16 variables. When a file has many POSIX ACL entries, the\naccumulated size can wrap past 65535, causing the pointer arithmetic\n(char *)pndace + *size to land within already-written ACEs. Subsequent\nwrites then overwrite earlier entries, and pndacl->size gets a\ntruncated value.\n\nUse check_add_overflow() at each accumulation point to detect the\nwrap before it corrupts the buffer, consistent with existing\ncheck_mul_overflow() usage elsewhere in smbacl.c."}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/smb/server/smbacl.c"],"versions":[{"version":"e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9","lessThan":"8d5729350b236896f51379588d9a690b7fafb8db","status":"affected","versionType":"git"},{"version":"e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9","lessThan":"e1955a94b6f17f4b058afa955a6f187eb3ed7615","status":"affected","versionType":"git"},{"version":"e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9","lessThan":"5e7b8f3c539d69b2ed5f2408e2f75e68ce7eef43","status":"affected","versionType":"git"},{"version":"e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9","lessThan":"ef7902be3f215b6bf7babe4dc9dd9a7d57dad7a7","status":"affected","versionType":"git"},{"version":"e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9","lessThan":"299f962c0b02d048fb45d248b4da493d03f3175d","status":"affected","versionType":"git"}]},{"product":"Linux","vendor":"Linux","defaultStatus":"affected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/smb/server/smbacl.c"],"versions":[{"version":"5.15","status":"affected"},{"version":"0","lessThan":"5.15","status":"unaffected","versionType":"semver"},{"version":"6.6.136","lessThanOrEqual":"6.6.*","status":"unaffected","versionType":"semver"},{"version":"6.12.84","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.18.25","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"7.0.2","lessThanOrEqual":"7.0.*","status":"unaffected","versionType":"semver"},{"version":"7.1-rc1","lessThanOrEqual":"*","status":"unaffected","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.15","versionEndExcluding":"6.6.136"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.15","versionEndExcluding":"6.12.84"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.15","versionEndExcluding":"6.18.25"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.15","versionEndExcluding":"7.0.2"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.15","versionEndExcluding":"7.1-rc1"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/8d5729350b236896f51379588d9a690b7fafb8db"},{"url":"https://git.kernel.org/stable/c/e1955a94b6f17f4b058afa955a6f187eb3ed7615"},{"url":"https://git.kernel.org/stable/c/5e7b8f3c539d69b2ed5f2408e2f75e68ce7eef43"},{"url":"https://git.kernel.org/stable/c/ef7902be3f215b6bf7babe4dc9dd9a7d57dad7a7"},{"url":"https://git.kernel.org/stable/c/299f962c0b02d048fb45d248b4da493d03f3175d"}],"title":"ksmbd: use check_add_overflow() to prevent u16 DACL size overflow","x_generator":{"engine":"bippy-1.2.0"}}}}