{"id":"CVE-2026-97554","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nsmb: client: avoid using uninitialized SIDs in cifs_posix_to_fattr()\n\ncifs_posix_to_fattr() ignores the return value of posix_info_parse().\nWhen a malformed POSIX direc…","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nsmb: client: avoid using uninitialized SIDs in cifs_posix_to_fattr()\n\ncifs_posix_to_fattr() ignores the return value of posix_info_parse().\nWhen a malformed POSIX direc…","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < c9a8b60ce140a68d172452f418137fc7ddbae7db","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < da6e25842431982d5a53cf00d925b98c690f4467","Linux < 7.2.7","Linux (all versions)"],"published":"2026-09-25","updated":"2026-09-25","sourceUpdated":"2026-09-25T11:17:05.860","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-97554","references":[{"url":"https://git.kernel.org/stable/c/c9a8b60ce140a68d172452f418137fc7ddbae7db","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/da6e25842431982d5a53cf00d925b98c690f4467","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"}],"tags":["nvd","cve.org"],"ingestedAt":"2026-09-25T11:06:38.917Z","slug":"CVE-2026-97554","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nsmb: client: avoid using uninitialized SIDs in cifs_posix_to_fattr()\n\ncifs_posix_to_fattr() ignores the return value of posix_info_parse().\nWhen a malformed POSIX directory entry is encountered (e.g. invalid\nSID lengths from an untrusted server), posix_info_parse() returns -1\nwithout populating the 'parsed' struct.  The uninitialized stack\nmemory in parsed.owner and parsed.group is then passed to\nsid_to_id(), which processes the garbage bytes and passes them to\nrequest_key() to construct a SID string, potentially leaking kernel\nstack contents to the userspace idmap daemon.\n\nFix this by checking the return value and skipping the SID-to-id\nmapping when parsing fails.  The remaining fattr fields (timestamps,\nmode, etc.) are populated directly from the 'info' pointer so they\nare unaffected.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}