Linux Kernel AIX Partition Array Bounds Overflow

CVE-2026-64318 is a buffer overflow vulnerability in the Linux kernel's AIX partition handling code. The vulnerability occurs when the aix_partition() function reads a physical volume descriptor (pvd) into a fixed-size struct and then iterates through its physical-partition-extent (ppe) array without properly validating that the declared pp_count value doesn't exceed the array's actual bounds. An attacker with the ability to provide a malicious AIX partition table could cause the kernel to read beyond allocated memory, potentially leading to information disclosure, denial of service, or privilege escalation. This affects any Linux system that attempts to mount or parse AIX-formatted disk partitions, making it relevant to enterprise environments and shared hosting platforms that handle diverse storage formats.

While CVE-2026-64318 has not yet mapped to specific MITRE ATT&CK techniques, Casky's security practitioners would identify this vulnerability through detection patterns associated with T1190 (Exploit Public-Facing Application) and T1203 (Exploitation for Client Execution) when analyzing kernel exploitation attempts. The attack would manifest as out-of-bounds memory access patterns during partition table parsing. Although Casky currently shows zero matching skills for this CVE, practitioners using Claude AI with extended reasoning would focus on detecting: (1) malformed partition table structures with inflated extent counts, (2) kernel memory access violations at predictable offsets within the pvd struct, and (3) system crashes or privilege escalation attempts correlating with partition mount operations. Real-time monitoring for these patterns would catch exploitation before the bounds check bypass could be leveraged.