CVE-2026-64318: Linux Kernel

High severity, CVSS 7.1. EPSS: 0.2% chance of exploitation in the next 30 days.

In the Linux kernel, the following vulnerability has been resolved: partitions: aix: bound the pp_count scan to the ppe array aix_partition() reads the physical volume descriptor into a fixed-size struct pvd and then scans its physical-partition-extent array: int numpps = be16_to_cpu(pvd->pp_count); ... for (i = 0; i < numpps; i += 1) { struct ppe *p = pvd->ppe + i; ... lp_ix = be16_to_cpu(p->lp_ix); pvd points at a single kmalloc()'d struct pvd whose ppe[] member holds a fixed ARRAY_SIZE(pvd->ppe) (1016) entries, but the loop runs up to the on-disk pp_count. pp_count is an unvalidated __be16 read straight from the descriptor, so a crafted AIX image with pp_count larger than 1016 drives the loop to read pvd->ppe[i] past the end of the allocation (up to 65535 entries, ~2 MB out of bounds). The partition scan runs without mounting anything, when a block device with a crafted AIX/IBM partition table appears (an attacker-supplied image attached with losetup -P, or a device auto-scanned by udev), via msdos_partition() -> aix_partition(). Clamp the scan to the number of entries the ppe[] array can hold.

Affected products

• Linux Linux Kernel: from 3.11, before 5.10.261 (fixed in 5.10.261); from 5.11, before 5.15.212 (fixed in 5.15.212); from 5.16, before 6.1.178 (fixed in 6.1.178); from 6.2, before 6.6.145 (fixed in 6.6.145); from 6.7, before 6.12.96 (fixed in 6.12.96); from 6.13, before 6.18.39 (fixed in 6.18.39); …

Published 2026-07-25. Last modified 2026-09-03.