Description

IBM AIX 7.2, and 7.3 and IBM PowerVM VIOS 4.1 could allow a local attacker to obtain root privileges due to improper enforcement of RBAC authentication roles.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "7.8",
  "pubDate": "2026-08-19T20:17:08.620Z",
  "pubdate": "2026-08-19T20:17:08.620Z",
  "executiveSummary": "A privilege escalation vulnerability exists in IBM AIX 7.2, 7.3, and IBM PowerVM VIOS 4.1 that permits a local attacker to acquire root privileges. The security flaw stems from the improper enforcement of Role-Based Access Control (RBAC) authentication roles within the affected operating system components.\nThe primary impact of successful exploitation is the complete compromise of system confidentiality, integrity, and availability, as the attacker achieves administrative root privileges. This vulnerability affects IBM AIX and IBM PowerVM VIOS instances operating with standard configurations where RBAC policies are inadequately validated or enforced.\nThe risk implications are severe, enabling unauthorized actors with local system access to bypass security boundaries and execute arbitrary administrative commands. Exploitation requirements dictate that the threat actor must already possess local access to the target system.\nThe attack capabilities allow a low-privileged local user to escalate their security context to the highest privilege level available on the host, facilitating full system control, data exfiltration, or the deployment of persistent system-level malware.",
  "technicalDetails": "The root cause of this vulnerability lies in the flawed implementation and verification logic of Role-Based Access Control (RBAC) authentication roles within IBM AIX 7.2, 7.3, and IBM PowerVM VIOS 4.1. Specifically, the system component responsible for enforcing RBAC role assignments fails to properly validate user credentials or authorization boundaries during specific privileged operations.\nThe vulnerable component involves the authorization and privilege management subsystems responsible for mediating access to restricted system resources and commands. Because authentication checks can be circumvented due to improper enforcement, a local user can invoke privileged functions without possessing the requisite authorized roles.\nRegarding authentication and privilege requirements, the attack requires local access to the target host. However, the attacker does not need prior administrative privileges, as the flaw specifically enables a standard, unprivileged user to bridge the authorization gap and elevate their execution context to root.\nThe attack vector is strictly local; network exposure is not a direct prerequisite for this specific privilege escalation vector, although it could be leveraged in a multi-stage attack where an initial remote access vector is used to establish a low-privileged local shell.\nThe step-by-step attack flow proceeds as follows: First, the local attacker obtains an unprivileged execution context on the target IBM AIX or IBM PowerVM VIOS system. Second, the attacker identifies and interacts with the vulnerable RBAC-protected binary, script, or system interface. Third, due to the improper enforcement of RBAC roles, the system fails to adequately verify if the executing user holds the required authorization. Fourth, the subsystem incorrectly grants access to the privileged function or command. Finally, the attacker executes arbitrary commands within the context of the root user, achieving complete administrative control over the operating system environment.\nThe post-exploitation impact includes unrestricted read, write, and execute capabilities across the entire file system, the ability to modify security configurations, create persistent backdoors, tamper with audit logs, and compromise any virtualized environments managed by the underlying IBM PowerVM VIOS instance."
}