Description

IBM AIX 7.2, and 7.3 and IBM PowerVM VIOS 4.1 NIM could allow a remote authenticated attacker to execute arbitrary commands due to improper neutralization of special elements used in an OS command.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "9.9",
  "pubDate": "2026-08-19T15:16:55.963Z",
  "pubdate": "2026-08-19T15:16:55.963Z",
  "executiveSummary": "This vulnerability involves an OS command injection flaw affecting IBM AIX 7.2, AIX 7.3, and IBM PowerVM VIOS 4.1 NIM (Network Installation Management). The weakness stems from improper neutralization of special elements used in operating system commands within the NIM component. A remote authenticated attacker can leverage this flaw to execute arbitrary OS commands on the underlying system, leading to unauthorized system access and potential compromise of confidentiality, integrity, and availability. Exploitation requires the attacker to possess valid authentication credentials and interact with the vulnerable NIM service. The risk implications are severe, as arbitrary command execution can allow attackers to escalate privileges, manipulate system configurations, or deploy malicious payloads within the affected environment.",
  "technicalDetails": "The vulnerability resides within the IBM AIX and IBM PowerVM VIOS Network Installation Management (NIM) subsystem, specifically in how user-supplied input or parameters are processed and passed to underlying operating system shell environments. The root cause is categorized as improper neutralization of special elements used in an OS command, commonly known as command injection. When input containing shell metacharacters or command separators is processed by the NIM component without adequate sanitization or escaping, the system inadvertently executes the appended attacker-supplied commands with the privileges of the executing NIM process.\nTo exploit this vulnerability, an attacker must first establish a valid authenticated session or interface with the vulnerable NIM service. Depending on the specific vector within NIM, the attacker transmits crafted requests containing malicious command sequences designed to break out of the intended application logic and interface directly with the underlying shell. The attack flow proceeds as follows: 1. The attacker authenticates to the target environment. 2. A specially crafted payload containing shell command syntax is submitted to the vulnerable NIM interface or parameter handling routine. 3. The NIM component fails to sanitize special characters properly. 4. The vulnerable function constructs an OS command string including the unsanitized input and passes it to the operating system shell for execution. 5. The arbitrary commands embedded in the payload are executed immediately by the OS, achieving remote code execution within the context of the vulnerable service.\nThe affected products and versions include IBM AIX 7.2, IBM AIX 7.3, and IBM PowerVM VIOS 4.1 NIM. The vulnerability requires remote authentication and appropriate access to the NIM subsystem to interact with the vulnerable input vectors. Post-exploitation impact includes full system compromise, data exfiltration, lateral movement within the network, and complete administrative control over the affected logical partitions or VIOS environments."
}