CVE Catalog

CVE-2026-89642

Low risk· EPSS 5%
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.16%

5th percentile - higher than 5% of all known CVEs

Summary

In the Linux kernel, cifs_setsize() omits pagecache_isize_extended() when extending a file. It calls truncate_pagecache() but skips zeroing the tail of the page straddling the old EOF, so dirty bytes in that region can be written back to the server, exposing stale data in the newly extended range. The fix adds pagecache_isize_extended() before truncate_pagecache().

Risk Assessment

Exposure of stale page cache data in the extended file range can lead to information disclosure. It affects systems using the CIFS/SMB client.

Recommendation

Update the Linux kernel to a version containing this fix. Avoid file extension operations on CIFS shares on unpatched systems.

Other vulnerabilities in Linux kernel

See all
Original NVD description (English source)

In the Linux kernel, the following vulnerability has been resolved: cifs: call pagecache_isize_extended() in cifs_setsize() when extending cifs_setsize() calls truncate_pagecache() but skips pagecache_isize_extended() on extension. truncate_setsize() shows the correct pattern: i_size_write(inode, newsize); if (newsize > oldsize) pagecache_isize_extended(inode, oldsize, newsize); truncate_pagecache(inode, newsize); pagecache_isize_extended() zeroes the tail of the page straddling old EOF. Without it, dirty bytes in that region can be written back to the server, exposing stale data in the newly extended range.

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