Description

IBM AIX 7.2, and 7.3 and IBM PowerVM VIOS 4.1 could allow a local attacker to gain elevated privileges due to an out-of-bounds write.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "8.4",
  "pubDate": "2026-08-20T22:17:17.773Z",
  "pubdate": "2026-08-20T22:17:17.773Z",
  "executiveSummary": "An out-of-bounds write vulnerability has been identified in IBM AIX 7.2 and 7.3, as well as IBM PowerVM VIOS 4.1. This vulnerability allows a local attacker to execute arbitrary code and achieve elevated privileges on the target operating system. The flaw presents a significant risk to confidentiality, integrity, and availability, as successful exploitation bypasses standard security boundaries and grants higher-level system access. Exploitation requires local system access, meaning an attacker must already possess a valid user account or execution context within the vulnerable environment. The root cause stems from improper boundary checking during memory write operations within the affected software components. Remediation requires applying the official software updates and patches provided by IBM to resolve the out-of-bounds write condition.",
  "technicalDetails": "The vulnerability is classified as an out-of-bounds write flaw affecting IBM AIX versions 7.2 and 7.3, alongside IBM PowerVM VIOS version 4.1. The root cause of the issue resides in insufficient bounds checking mechanisms when processing specific inputs or memory buffer operations within kernel or privileged system components. A local attacker with low-privileged access can interact with the vulnerable subsystem or system call interface, supplying specially crafted input designed to exceed allocated buffer boundaries. When the system processes this input, a memory write occurs past the designated buffer limit, leading to memory corruption. This corruption can overwrite adjacent critical kernel data structures, function pointers, or control flow registers. By carefully orchestrating the layout of the heap or stack prior to triggering the out-of-bounds write, the attacker can hijack control flow and redirect execution to arbitrary payload code. The exploitation sequence involves authentication to the local operating system, preparation of the malicious input vector, interaction with the vulnerable system interface to trigger the write condition, and subsequent execution of code with elevated privileges. Because the vulnerability resides within core operating system components handling low-level memory operations, exploitation results in full system compromise. Network exposure is not strictly required for initial access, as the attack vector is local, but it may be leveraged subsequently for post-exploitation activities such as lateral movement or data exfiltration."
}