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 stack-based buffer overflow.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "7.8",
  "pubDate": "2026-08-20T22:17:08.643Z",
  "pubdate": "2026-08-20T22:17:08.643Z",
  "executiveSummary": "A stack-based buffer overflow vulnerability has been identified in IBM AIX 7.2, IBM AIX 7.3, and IBM PowerVM VIOS 4.1. This vulnerability allows a localized attacker to execute arbitrary code within the context of the affected system.\nThe flaw stems from insufficient bounds checking when handling input data, enabling a local threat actor to corrupt the stack memory space. Successful exploitation compromises the confidentiality, integrity, and availability of the host operating system.\nThe attack vector requires local access to the target system and appropriate privileges to interact with the vulnerable component. No specific exploitation requirements beyond local execution capabilities are detailed in the disclosure.\nThe risk implications are severe, as arbitrary code execution at the local level can lead to full system compromise, privilege escalation, and unauthorized access to sensitive data stored on the affected IBM AIX and PowerVM VIOS environments.",
  "technicalDetails": "The root cause of the vulnerability is a classic stack-based buffer overflow condition present in the affected software components of IBM AIX and IBM PowerVM VIOS. This occurs when the application copies untrusted input into a fixed-size stack buffer without performing adequate length validation.\nThe vulnerable component processes input data insecurely, allowing an attacker to overflow the designated buffer boundaries and overwrite adjacent stack memory. This typically includes critical control data such as saved frame pointers and return addresses.\nExploitation requires the attacker to possess local access to the vulnerable system. The attacker crafts a malicious payload containing shellcode and precise padding to overwrite the return address on the stack. When the vulnerable function attempts to return execution control, the instruction pointer is redirected to the attacker-supplied payload.\nThe attack flow proceeds as follows: first, the local attacker interacts with the vulnerable binary or system interface exposed by IBM AIX 7.2, 7.3, or IBM PowerVM VIOS 4.1. Second, the attacker supplies oversized input designed to breach the stack buffer allocation. Third, memory corruption occurs, overwriting control structures. Finally, execution flow is hijacked, allowing the arbitrary code to execute with the privileges of the exploited process.\nAuthentication requirements are limited to local system access, and the privilege requirements depend on the execution context of the vulnerable binary. Network exposure is non-existent as the vulnerability is strictly exploitable locally.\nPost-exploitation impact includes complete system takeover, arbitrary command execution, potential privilege escalation to root or hypervisor level privileges, and the installation of persistent malicious backdoors within the IBM AIX or PowerVM VIOS environment."
}