CVE-2026-97554
In the Linux kernel, the following vulnerability has been resolved: smb: client: avoid using uninitialized SIDs in cifs_posix_to_fattr() cifs_posix_to_fattr() …
Impact
In the Linux kernel, the following vulnerability has been resolved: smb: client: avoid using uninitialized SIDs in cifs_posix_to_fattr() cifs_posix_to_fattr() ignores the return value of posix_info_parse(). When a malformed POSIX directory entry is encountered (e.g. invalid SID lengths from an untrusted server), posix_info_parse() returns -1 without populating the 'parsed' struct. The uninitialized stack memory in parsed.owner and parsed.group is then passed to sid_to_id(), which processes the garbage bytes and passes them to request_key() to construct a SID string, potentially leaking kernel stack contents to the userspace idmap daemon. Fix this by checking the return value and skipping the SID-to-id mapping when parsing fails. The remaining fattr fields (timestamps, mode, etc.) are populated directly from the 'info' pointer so they are unaffected.
Affected packages
This record carries no package version data, so it cannot be matched against a dependency list automatically. Read the advisory and compare your version by hand.
References
- NVD record
- CVE.org record
- https://git.kernel.org/stable/c/1915b69e36906968e2b698699d0f219875ae846e
- https://git.kernel.org/stable/c/2be31f252ade791b84f7164991f14436aed1d4b9
- https://git.kernel.org/stable/c/33106019c3be57b5fc6411cfaad6d98214a51265
- https://git.kernel.org/stable/c/604feb3e8141bf11f5afd48d36d401fee5af9536
- https://git.kernel.org/stable/c/c9a8b60ce140a68d172452f418137fc7ddbae7db
- https://git.kernel.org/stable/c/da6e25842431982d5a53cf00d925b98c690f4467