Description

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

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "8.5",
  "pubDate": "2026-08-20T22:17:14.890Z",
  "pubdate": "2026-08-20T22:17:14.890Z",
  "executiveSummary": "A stack-based buffer overflow vulnerability exists in IBM AIX 7.2 and 7.3, as well as IBM PowerVM VIOS 4.1. This vulnerability allows a remote authenticated attacker to execute arbitrary code on targeted systems.\nThe primary impact of successful exploitation is complete compromise of system integrity and confidentiality, as arbitrary code execution at elevated privilege levels often permits full system takeover.\nThe affected products include IBM AIX versions 7.2 and 7.3, alongside IBM PowerVM VIOS version 4.1. The risk implication is severe, presenting significant threats to enterprise environments utilizing these operating systems and virtualization platforms.\nTo execute an attack, the threat actor must possess valid authentication credentials to the target system. The specific attack vector relies on interacting with the vulnerable component in a manner that supplies input exceeding allocated buffer boundaries on the stack.\nGiven the requirement for remote authentication, unauthorized unauthenticated external entities cannot directly trigger the vulnerability without prior access compromise. However, insider threats or compromised user accounts present viable vectors for exploitation.",
  "technicalDetails": "The root cause of the vulnerability is a stack-based buffer overflow condition residing within specific internal components of IBM AIX 7.2, 7.3, and IBM PowerVM VIOS 4.1. A stack-based buffer overflow occurs when a program writes more data to a buffer located on the stack than what is actually allocated for storage. This typically happens due to insufficient bounds checking on user-supplied input prior to memory copy operations.\nThe vulnerable component processes input streams or parameters without properly validating the length of the incoming data relative to the destination buffer size. When an authenticated attacker submits a maliciously crafted payload that exceeds the expected byte length, the excess data overflows the bounds of the stack buffer.\nThis overflow overwrites adjacent stack memory structures, which commonly include saved frame pointers and return addresses. By precisely controlling the overflow data, an attacker can overwrite the saved return address with a memory pointer directed toward malicious shellcode or utilize techniques such as return-oriented programming to bypass mitigation controls.\nThe exploitation flow proceeds as follows: First, the remote attacker establishes an authenticated session or interface channel with the vulnerable service or binary. Second, the attacker formulates a payload containing excessive data designed to trigger the boundary violation. Third, the attacker transmits this payload to the vulnerable component. Fourth, the application processes the input, copying the oversized data into a fixed-size stack buffer without adequate length verification. Fifth, the stack becomes corrupted, overwriting the execution control data. Finally, upon function return, the instruction pointer is redirected to the attacker-supplied payload, resulting in the execution of arbitrary code within the context of the running process.\nThe attack requirements mandate that the threat actor is authenticated, meaning anonymous exploitation is precluded. Depending on the execution context of the vulnerable process, the resulting arbitrary code execution may inherit elevated privileges, potentially leading to root or administrative control over the affected IBM AIX or IBM PowerVM VIOS instance.\nPost-exploitation impact includes unauthorized execution of administrative commands, installation of persistent backdoors, lateral movement within the network, data exfiltration, and manipulation of system configurations."
}