Description

IBM AIX 7.2, and 7.3 and IBM PowerVM VIOS 4.1 could allow a remote attacker to obtain sensitive information and cause a denial of service due to a kernel heap over-read.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "8.1",
  "pubDate": "2026-08-20T22:17:12.023Z",
  "pubdate": "2026-08-20T22:17:12.023Z",
  "executiveSummary": "A kernel heap over-read vulnerability has been identified in IBM AIX 7.2, IBM AIX 7.3, and IBM PowerVM VIOS 4.1. This vulnerability allows a remote attacker to obtain sensitive information and trigger a denial of service condition.\nThe flaw resides within the kernel memory management subsystem, specifically involving improper bounds checking during heap-based operations. Successfully exploiting this vulnerability compromises the confidentiality and availability of the affected system, potentially leaking kernel memory contents that could aid in further compromise or causing system instability leading to a denial of service.\nThe risk implication is severe due to the core operating system and hypervisor nature of the affected platforms, impacting virtualized environments and underlying host integrity. Attack capabilities include unauthorized memory inspection and service disruption. Exploitation requirements involve network-based interaction with the vulnerable kernel component, though specific authentication or privilege requirements depend on the exact vector exposed by the service handling the malformed input.\nOrganizations utilizing the specified versions of IBM AIX and IBM PowerVM VIOS must prioritize applying official vendor remediations to neutralize the exposure.",
  "technicalDetails": "The vulnerability is classified as a kernel heap over-read, stemming from insufficient validation of input lengths or buffer boundaries within kernel-level data processing routines in IBM AIX 7.2, IBM AIX 7.3, and IBM PowerVM VIOS 4.1.\nThe vulnerable component resides in the operating system kernel, specifically handling protocol parsing or system calls where dynamic memory allocation on the heap occurs. When processing specially crafted requests, the kernel routines fail to correctly verify the size of the data being read relative to the allocated buffer boundary.\nDuring exploitation, an attacker transmits a maliciously crafted payload over the network to the vulnerable service or subsystem exposed by the kernel. As the kernel parses the input, it reads past the intended boundary of the heap allocation, accessing adjacent memory locations. This over-read condition allows the attacker to extract sensitive kernel memory contents, which may include kernel pointers, cryptographic material, or other internal data structures returned in subsequent responses or error conditions.\nFurthermore, if the heap over-read attempts to access unmapped memory pages or corrupts internal memory management metadata during the out-of-bounds read operation, it triggers a kernel panic or exception, resulting in a denial of service for the host operating system or the IBM PowerVM VIOS environment.\nThe attack flow requires network connectivity to the affected target. Depending on the specific exposed interface, exploitation may be achieved remotely over the network without prior authentication or may require specific low-level privileges, directly compromising the kernel execution domain and destabilizing the host platform."
}