CVE-2024-27260: IBM AIX and VIOS RCE Vulnerability

CVE-2024-27260 Overview

CVE-2024-27260 is a local privilege escalation vulnerability affecting the invscout command in IBM AIX and IBM VIOS. A non-privileged local user can exploit the flaw to execute arbitrary commands on the host. IBM tracks this issue as X-Force ID 283985. The vulnerability is categorized under CWE-250: Execution with Unnecessary Privileges, indicating that the invscout binary runs with more privileges than required for its intended function.

Critical Impact
An authenticated local user can escalate privileges through the invscout command and execute arbitrary commands, compromising confidentiality, integrity, and availability of affected AIX and VIOS systems.

Affected Products

IBM AIX 7.2
IBM AIX 7.3
IBM VIOS 3.1 and VIOS 4.1

Discovery Timeline

2024-05-16 - CVE-2024-27260 published to NVD
2026-06-17 - Last updated in NVD database

Technical Details for CVE-2024-27260

Vulnerability Analysis

The invscout command is an AIX utility that surveys installed microcode and firmware levels on the system. It is typically installed as a setuid binary so it can access hardware inventory data reserved for privileged users. Because the command executes with elevated privileges, any unsafe operation performed by the binary becomes a privilege escalation primitive.

A local, non-privileged user invoking invscout can leverage the flaw to run arbitrary commands in the security context of the privileged process. The result is full compromise of the host, including read and write access to sensitive files and the ability to modify system state on both AIX and VIOS deployments.

Root Cause

The root cause is classified as CWE-250: Execution with Unnecessary Privileges. The invscout binary retains elevated privileges while performing operations that accept attacker-influenced input. IBM has not publicly disclosed the precise code path. See the IBM Support Advisory and the IBM X-Force Vulnerability Report for vendor-supplied technical detail.

Attack Vector

Exploitation requires local access to a vulnerable AIX or VIOS host with the ability to execute the invscout command. No authentication to the vulnerable component itself is required beyond a valid shell on the system. The attacker invokes invscout in a manner that causes the privileged process to execute attacker-chosen commands, bypassing normal access controls.

No public proof-of-concept exploit is currently listed for this CVE, and it is not present in the CISA Known Exploited Vulnerabilities catalog.

Detection Methods for CVE-2024-27260

Indicators of Compromise

Execution of /usr/sbin/invscout by non-administrative user accounts, especially with unusual arguments or environment variables.
Child processes spawned by invscout that are not part of its normal firmware inventory workflow (for example, shells, sh, ksh, or scripting interpreters).
Unexpected modifications to files owned by root following invscout execution by a standard user.

Detection Strategies

Enable AIX audit subsystem (audit) events for PROC_Execute and monitor invocations of invscout by non-root UIDs.
Correlate invscout executions with subsequent privileged file writes or user/group changes on the same host.
Baseline legitimate administrative use of invscout and alert on deviations in parent process, working directory, or command arguments.

Monitoring Recommendations

Forward AIX and VIOS audit logs and syslog to a centralized logging platform for retention and correlation.
Track setuid binary usage across AIX and VIOS hosts and alert on privilege escalation patterns following invscout execution.
Review VIOS padmin command history for indirect invocations of invscout or related firmware survey tooling.

How to Mitigate CVE-2024-27260

Immediate Actions Required

Apply the IBM-provided fixes referenced in the IBM Support Advisory for affected AIX 7.2, AIX 7.3, VIOS 3.1, and VIOS 4.1 levels.
Inventory all AIX and VIOS systems and confirm patch status of the invscout fileset (invscout.rte).
Restrict interactive local access on affected hosts to trusted administrators until patches are applied.

Patch Information

IBM has released official interim fixes and service pack updates for AIX 7.2, AIX 7.3, VIOS 3.1, and VIOS 4.1. Refer to the IBM Support Advisory for exact fileset levels, download links, and verification instructions. Confirm the installed fix using emgr -l or instfix -ik after applying the update.

Workarounds

If patching is not immediately feasible, remove the setuid bit from /usr/sbin/invscout to prevent unprivileged users from invoking it with elevated privileges, understanding that this disables firmware survey functionality for non-root users.
Limit shell access on affected AIX and VIOS systems to administrators only, using role-based access controls (RBAC) and restricted VIOS padmin shells.
Monitor for and remove any local user accounts that no longer require access to affected systems.

bash

# Verify installed invscout fileset and applied interim fixes
lslpp -L invscout.rte
emgr -l

# Optional hardening: remove setuid bit until patch is applied
# (this disables invscout for non-root users)
ls -l /usr/sbin/invscout
chmod u-s /usr/sbin/invscout