CVE-2023-53593: 
Linux Kernel vulnerability analysis and mitigation

CVE-2023-53593 is a vulnerability in the Linux kernel related to a folio lock release issue in the CIFS filesystem. The vulnerability was disclosed on October 4, 2025. The issue affects the cifs_readpage_worker functionality when interacting with fscache (NVD).

The vulnerability occurs when cifs_readpage_worker is called, where the call contract requires the callee to unlock the page. According to the documentation in Documentation/filesystems/vfs.rst, the filesystem should unlock the folio once the read has completed, regardless of success or failure. When fscache is in use and a cache hit occurs during a read, the page lock is leaked. While cifs_readpage_from_fscache marks the page clean in __cifs_readpage_from_fscache on success, it does not free the folio lock (NVD).

When the vulnerability is triggered, it results in a deadlock condition that requires a system reboot to resolve. The issue manifests when subsequent reads (via mmap) attempt to access the affected page, leading to a stuck process that cannot proceed (NVD).

The vulnerability has been fixed in various Linux distributions. Debian has released fixes in multiple versions: bullseye (5.10.244-1), bookworm (6.1.153-1), trixie (6.12.48-1), and sid (6.16.12-2) (Debian Tracker).