The Linux kernel’s netfs module can leave stale pagecache entries after an EOF when a file is extended by an ordinary write. Dirty data written past the original file end by an mmap mapping is not cleared by the buffered or unbuffered write paths. This stale content can remain visible to subsequent accesses, potentially exposing data that should not be accessible after the file’s logical size has increased. The flaw belongs to mismanagement of pagecache data rather than a classic injection or privilege escalation.

All Linux kernel builds that provide the netfs filesystem and have not incorporated the commit that zeros stale pagecache pages hold the vulnerability. The CNA information lists Linux as the affected product but no specific kernel versions or release dates are supplied, so any unpatched kernel containing the generic netfs implementation is potentially impacted.

The CVSS score of 3.3 indicates low overall severity, and the EPSS score of less than 1% suggests a very low likelihood of exploitation. Based on the description, it is inferred that an attacker would need local access to a netfs mount and the ability to perform an extending write to leverage the stale pagecache. The vulnerability is not remotely exploitable from a network interface, but a local user with write privileges to the affected filesystem could read stale data that was previously written past EOF via mmap. The flaw is not listed in the CISA KEV catalog and therefore no widespread attacks are currently documented.