Description

IBM AIX 7.2, and 7.3 and IBM PowerVM VIOS 4.1 could allow a remote attacker to execute arbitrary code due to a stack buffer overflow.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "9.8",
  "pubDate": "2026-08-19T20:17:11.173Z",
  "pubdate": "2026-08-19T20:17:11.173Z",
  "executiveSummary": "This vulnerability is classified as a stack buffer overflow, which poses a severe risk to system integrity and confidentiality. The flaw resides in IBM AIX versions 7.2 and 7.3, as well as IBM PowerVM VIOS version 4.1. If successfully exploited, a remote attacker can execute arbitrary code within the context of the vulnerable application or operating system component.\nThe risk implication is critical, as successful exploitation could lead to full system compromise, allowing unauthorized actors to bypass security controls, manipulate sensitive data, or disrupt critical operational services. The attack capabilities involve remote execution vectors, enabling malicious entities to interact with the target systems across a network without requiring prior physical access.\nWhile specific exploitation requirements such as authentication details or specialized configuration states are not explicitly detailed in the baseline description, stack buffer overflows typically require crafting a specialized payload designed to overwrite memory structures on the stack, such as return addresses or function pointers, thereby redirecting the execution flow to attacker-controlled instructions.\nOrganizations operating the affected IBM AIX and PowerVM VIOS versions must treat this vulnerability with high priority, initiating immediate vulnerability management workflows to assess exposure and apply vendor-supplied patches or workarounds as soon as they become available.",
  "technicalDetails": "The vulnerability is fundamentally rooted in unsafe memory management practices within the affected components of IBM AIX 7.2, 7.3, and IBM PowerVM VIOS 4.1. Specifically, a stack buffer overflow occurs when an application or system service writes data to a memory buffer located on the stack without adequately validating the size of the incoming data against the allocated capacity of the destination buffer.\nWhen excessively sized input is processed by the vulnerable function, the boundary constraints are violated, causing the excess data to overflow the designated stack buffer. This overflow sequentially overwrites adjacent stack memory regions, which routinely contain critical execution context data, including saved frame pointers and return addresses.\nDuring the attack flow, a remote threat actor transmits a maliciously crafted payload across the network to the targeted service running on IBM AIX or IBM PowerVM VIOS. Upon receipt, the vulnerable component processes the input, triggering the buffer overflow condition as the payload data spills past the boundaries of the stack-allocated buffer.\nAs the execution flow reaches the end of the vulnerable function, the processor attempts to restore the saved return address from the stack to resume normal operations. Because this address has been overwritten by the attacker's payload, the instruction pointer is redirected to a memory location chosen by the attacker, which typically points to shellcode or a return-oriented programming (ROP) chain embedded within the payload.\nUpon successful redirection, the payload executes with the privileges of the compromised process. Depending on the execution context of the vulnerable service, this may range from unprivileged user access to highly privileged system-level execution. Post-exploitation impact includes arbitrary command execution, installation of persistent backdoors, lateral movement within the network, and complete administrative control over the affected IBM AIX or PowerVM VIOS environment."
}