Description

IBM AIX 7.2, and 7.3 and IBM PowerVM VIOS 4.1 could allow a remote attacker to cause a denial of service due to a null pointer dereference.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "6.5",
  "pubDate": "2026-08-19T20:17:05.987Z",
  "pubdate": "2026-08-19T20:17:05.987Z",
  "executiveSummary": "A null pointer dereference vulnerability exists within IBM AIX 7.2 and 7.3, as well as IBM PowerVM VIOS 4.1. This vulnerability allows an unauthenticated remote attacker to induce a denial of service condition against the affected system. The root mechanism involves improper handling of specific operations, leading to an abnormal termination of critical services or the operating system kernel upon dereferencing an uninitialized or null memory pointer. The risk implication is significant due to the potential for service disruption affecting availability across enterprise environments utilizing these operating systems and virtualization platforms. Exploitation requirements involve network connectivity to the target system, leveraging the flaw to crash services without requiring prior privileges or user interaction. Given the remote vector and lack of prerequisite authentication, attackers can trigger the denial of service state efficiently, impacting system stability and business continuity.",
  "technicalDetails": "The vulnerability is characterized by a null pointer dereference flaw residing within the core architectural components of IBM AIX 7.2, IBM AIX 7.3, and IBM PowerVM VIOS 4.1. A null pointer dereference occurs when the application or kernel attempts to read or write memory through a pointer that does not point to a valid memory address, typically holding a NULL value (0x0). In this specific context, the vulnerable component fails to adequately validate input parameters or internal state pointers prior to memory access operations during network communication or packet processing routines.\nThe attack flow proceeds as follows: A remote attacker, operating with network exposure to the vulnerable host, transmits a maliciously crafted network payload or request directed at the affected service daemon or kernel interface. Upon receipt, the parsing or handling routines process the input data in a manner that triggers an unexpected execution path. Within this execution path, a pointer intended to reference a dynamically allocated structure or control block remains uninitialized or is improperly reset to null. When the underlying code logic attempts to access members of this structure via the null pointer, the CPU generates a hardware trap or segmentation fault.\nBecause this error occurs within critical execution contexts—potentially involving kernel-level processes or essential system daemons—the operating system cannot recover gracefully. Consequently, the exception results in an immediate system panic, kernel crash, or abrupt termination of the targeted service, precipitating a denial of service condition. Authentication and privilege requirements are absent for this remote attack vector, as the flaw is reachable prior to session establishment or through publicly accessible service endpoints. Post-exploitation impact is strictly limited to availability disruption; arbitrary code execution or privilege escalation is generally not facilitated by standard null pointer dereference vulnerabilities of this nature, though continuous disruption can severely degrade operational infrastructure."
}