Description

IBM AIX 7.2, and 7.3 and IBM PowerVM VIOS 4.1 could allow a local attacker to execute arbitrary code due to a heap-based buffer overflow.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "8.2",
  "pubDate": "2026-08-20T22:17:08.313Z",
  "pubdate": "2026-08-20T22:17:08.313Z",
  "executiveSummary": "This vulnerability is classified as a heap-based buffer overflow affecting IBM AIX 7.2, 7.3, and IBM PowerVM VIOS 4.1. The flaw resides in the handling of internal data structures within the affected operating system environments, allowing a locally authenticated attacker to execute arbitrary code with elevated privileges. The primary impact of this vulnerability is the complete compromise of system integrity and confidentiality, as successful exploitation enables full control over the targeted operating system instance. Risk implications are severe due to the potential for unauthorized privilege escalation and subsequent system-wide disruption within virtualized and bare-metal Power Systems environments. Exploitation requirements dictate that the adversary must already possess local access to the vulnerable system. No specific network exposure or remote attack vector is required for this vulnerability to be weaponized, limiting initial access requirements while presenting significant risk once a local foothood is established.",
  "technicalDetails": "The vulnerability is fundamentally rooted in a heap-based buffer overflow within the memory management routines of IBM AIX 7.2, 7.3, and IBM PowerVM VIOS 4.1. Specifically, the flaw occurs when the vulnerable component fails to properly validate the boundaries of input data copied into heap-allocated memory buffers. Without adequate bounds checking, excessively sized input or specially crafted sequences supplied to the vulnerable interface result in heap corruption, overwriting adjacent heap metadata or critical control data structures.\nThe attack flow begins with the local attacker authenticating to the target system. Utilizing local execution vectors, the adversary interacts with the vulnerable subsystem or application programming interface (API) that handles the flawed memory allocation routine. By supplying a maliciously crafted payload designed to exceed the allocated heap buffer size, the attacker corrupts the heap layout. This corruption can be leveraged to manipulate function pointers, virtual method tables, or dynamic memory management structures.\nUpon successful manipulation of the heap structures, the execution flow is diverted to attacker-controlled shellcode or arbitrary machine instructions provided within the payload. Because the vulnerable code typically executes within the context of privileged system components or daemons, the resulting code execution inherits these elevated privileges. Privilege requirements are limited to local access, and authentication requirements depend on the specific interface exposing the vulnerable code path. The post-exploitation impact includes arbitrary code execution, persistence installation, escalation to root or hypervisor-level privileges, and the ability to compromise underlying logical partitions or virtualized workloads managed by IBM PowerVM VIOS."
}