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 an out-of-bounds write.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "9.8",
  "pubDate": "2026-08-19T20:17:05.200Z",
  "pubdate": "2026-08-19T20:17:05.200Z",
  "executiveSummary": "This vulnerability involves an out-of-bounds write flaw affecting IBM AIX 7.2, IBM AIX 7.3, and IBM PowerVM VIOS 4.1. The security defect allows a remote attacker to achieve arbitrary code execution on targeted systems.\nThe primary impact of successful exploitation is a complete compromise of confidentiality, integrity, and availability of the affected operating system or virtualization environment. Given the remote attack vector, unauthorized actors can potentially interact with vulnerable network-exposed services or components to trigger memory corruption conditions.\nThe risk implications are severe, as unauthorized remote code execution on core infrastructure platforms like AIX and PowerVM VIOS typically grants high-level administrative privileges, enabling lateral movement, data exfiltration, and persistent system disruption within enterprise environments.\nRemediation requires applying official vendor-supplied security fixes and patches as soon as they become available from IBM, alongside implementing network segmentation and hardening best practices to restrict unauthorized access to sensitive system services.",
  "technicalDetails": "The vulnerability is rooted in an out-of-bounds write memory corruption flaw present in IBM AIX versions 7.2 and 7.3, as well as IBM PowerVM VIOS version 4.1.\nAn out-of-bounds write occurs when software writes data past the end, or before the beginning, of the intended buffer or memory region. This condition typically arises from insufficient boundary checking, incorrect arithmetic calculations when determining buffer sizes, or improper handling of untrusted input lengths during memory allocation and manipulation operations.\nIn the context of the affected IBM products, exploitation takes place when a remote attacker sends specially crafted input or network payloads designed to interact with vulnerable internal components or parsing routines. As the software processes the malformed data, it writes beyond the allocated boundaries of a heap or stack buffer, overwriting adjacent memory structures, function pointers, or control data.\nBy carefully controlling the content of the out-of-bounds write, an attacker can manipulate critical execution flow pointers, enabling the redirection of CPU execution to attacker-supplied shellcode or Return-Oriented Programming (ROP) chains.\nThe attack flow requires network connectivity to the vulnerable service or daemon handling the input processing. Depending on the specific component exposed, the attack may not require prior authentication, allowing unauthenticated remote adversaries to leverage the memory corruption flaw directly.\nSuccessful execution of arbitrary code grants the attacker the execution context and privileges of the compromised process, which frequently includes root or hypervisor-level privileges in the case of core operating system and VIOS components.\nPost-exploitation activities can include installing persistent backdoors, escalating privileges further if necessary, intercepting sensitive data, manipulating system configurations, and disrupting critical virtualized workloads managed by IBM PowerVM VIOS."
}