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 and potentially disclose sensitive information due to an integer underflow.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "8.2",
  "pubDate": "2026-08-20T22:17:16.430Z",
  "pubdate": "2026-08-20T22:17:16.430Z",
  "executiveSummary": "This vulnerability is classified as an integer underflow flaw affecting specific enterprise Unix and virtualization platforms.\nThe primary impact of successful exploitation includes a localized or remote denial of service against the targeted system, as well as the potential unauthorized disclosure of sensitive system information.\nThe affected products comprise IBM AIX versions 7.2 and 7.3, alongside IBM PowerVM VIOS version 4.1.\nThe risk implications are severe for enterprise environments relying on these operating systems and hypervisors, as system availability and data confidentiality are directly compromised.\nAn unauthenticated remote attacker with network access to vulnerable services can leverage this weakness without requiring prior administrative privileges.\nExploitation relies on manipulating input parameters processed by vulnerable routines to induce an arithmetic underflow condition, destabilizing memory operations and exposing adjacent memory regions or crashing the target process.",
  "technicalDetails": "The root cause of the vulnerability stems from an arithmetic calculation flaw, specifically an integer underflow, occurring during the processing of untrusted input data within the affected software components of IBM AIX and IBM PowerVM VIOS.\nWhen the application or operating system kernel processes maliciously crafted input payloads, mathematical operations compute a value falling below the minimum representable limit of the data type without proper bounds checking or validation.\nThis resulting wrap-around or underflowed value is subsequently utilized as a size parameter in memory allocation routines, buffer slicing, or index calculations.\nThe attack flow begins when a remote attacker transmits a specially crafted network packet or request interacting with the vulnerable service exposed by the target system.\nUpon receipt, the vulnerable component parses the input, triggering the flawed arithmetic operation and generating an invalid memory offset or excessively large allocation size.\nExploitation behavior can manifest in two primary ways depending on the subsequent memory operation: either causing an out-of-bounds read that leaks sensitive kernel or process memory back to the attacker, or triggering a segmentation fault and application panic resulting in a denial of service.\nThe affected components reside within the networking stack or system daemons of IBM AIX 7.2, AIX 7.3, and IBM PowerVM VIOS 4.1.\nThe vulnerability is exposed over the network, allowing remote attackers to initiate exploitation without local shell access or prior authentication.\nNo specific privilege requirements are documented for initiating the attack vector, making network accessibility the primary prerequisite for threat actors targeting this flaw."
}