Description

IBM i 7.6, 7.5, 7.4, and 7.3 could allow a remote authenticated attacker to execute arbitrary code due to a heap-based buffer overflow.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "8.8",
  "pubDate": "2026-08-13T20:17:17.240Z",
  "pubdate": "2026-08-13T20:17:17.240Z",
  "executiveSummary": "A heap-based buffer overflow vulnerability exists in IBM i 7.6, 7.5, 7.4, and 7.3.\nThe vulnerability allows a remote authenticated attacker to execute arbitrary code on vulnerable systems.\nThe flaw stems from improper boundary checking during memory allocation and data processing within the affected component.\nSuccessful exploitation of this security defect compromises the confidentiality, integrity, and availability of the underlying operating system.\nAn attacker must possess valid authentication credentials to interact with the vulnerable service and deliver a specially crafted payload.\nDue to the capability of arbitrary code execution, this issue poses a severe risk to enterprise environments relying on the affected IBM i versions.",
  "technicalDetails": "The vulnerability is classified as a heap-based buffer overflow affecting IBM i versions 7.6, 7.5, 7.4, and 7.3.\nThe root cause involves inadequate bounds validation when handling input data allocated within the heap memory region.\nAttack requirements dictate that the adversary must be authenticated to the target system and able to establish network communication with the vulnerable daemon or service.\nThe attack flow begins when the authenticated attacker transmits a maliciously crafted request containing oversized data designed to exceed the allocated heap buffer size.\nAs the vulnerable component processes the input, the unchecked data overflows the heap boundary, overwriting adjacent memory structures, control blocks, or function pointers.\nBy carefully structuring the input payload, the attacker can manipulate the overwritten memory regions to redirect execution flow to shellcode or malicious instructions supplied within the payload.\nBecause the execution occurs within the context of the vulnerable service or system process, the attacker achieves arbitrary code execution with the privileges associated with that process.\nPost-exploitation impact includes full system compromise, escalation of privileges, unauthorized data access, and potential lateral movement within the network depending on the privilege level of the compromised process."
}