In the Linux kernel, netfs_perform_write mistakenly disables the write‑streaming optimization when a file descriptor is opened with O_RDWR, as well as when fscache or content encryption is active. Write‑streaming caches dirty pages that are not yet up‑to‑date to avoid expensive reads of data that is about to be overwritten; the incorrect disabling resulted in unnecessary performance penalties and, in certain scenarios, read/write inconsistencies. This issue was identified during the generic/522 xfstest workload and has since been resolved in upstream code.

The flaw affects all Linux kernel versions released prior to the commit that removes the O_RDWR check in netfs_perform_write. The affected products include every Linux kernel distributable (as indicated by the CPE strings for linux:linux_kernel and the various 7.1 release candidates).

The CVSS score of 7.3 reflects a high severity potential for degradation of I/O performance and consistency, but the EPSS score of less than 1% and absence from the CISA KEV catalog indicate a low likelihood of real‑world exploitation. Based on the description, it is inferred that the vulnerability can be triggered by any local process that performs file operations through the netfs subsystem, but no public exploitation is known.