CVE Catalog

CVE-2026-97554

Unknown
Published: Translated: NVD NIST

Summary

In the Linux kernel's SMB client, cifs_posix_to_fattr() ignores the return value of posix_info_parse(), which can lead to using uninitialized SIDs and potentially leaking kernel stack data to the ID mapping process. The fix checks the return value and skips SID mapping on parsing failure.

Risk Assessment

Potential information leak from kernel to userspace and system instability.

Recommendation

Apply the patch that checks posix_info_parse() result and skips SID mapping on error.

Other vulnerabilities in Linux kernel

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Original NVD description (English source)

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.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS