A flaw in the Linux kernel’s procfs implementation allows the build ID of a mapped file to be fetched while holding critical locks on the virtual memory area (VMA). This can cause a deadlock between the mmap lock and the inode mutex during read operations. Based on the description, it is inferred that an attacker could trigger the deadlock by invoking the procmap ioctl interface, which could freeze the kernel or hang involved processes, resulting in a denial of service.

All Linux kernel releases that include the vulnerable procfs code, notably kernel versions 6.19 and its release candidates up to 6.19rc8, are affected. The issue is present in the kernel tree prior to the commit that moves build ID fetching out of the VMA lock region.

The CVSS score of 5.5 indicates moderate severity, and the EPSS probability is less than 1%, pointing to a low likelihood of widespread exploitation at present. The vulnerability is not listed in the CISA KEV catalog. Based on the description, it is inferred that the attack vector is local, requiring a user to issue the procmap ioctl request that triggers the deadlock. Based on the description, it is inferred that there is no remote code execution risk. A successful exploit can permanently halt the kernel or hang critical processes until a reboot occurs.