CVE-2026-14976 Overview
CVE-2026-14976 affects IBM WebSphere Application Server - Liberty versions 17.0.0.3 through 26.0.0.8. The vulnerability allows remote code execution when the collectiveController-1.0 feature is enabled. The flaw stems from missing authentication for a critical function [CWE-306], allowing attackers on the adjacent network to execute arbitrary code against a vulnerable server instance.
Critical Impact
Successful exploitation enables adjacent-network attackers to achieve remote code execution on IBM WebSphere Liberty servers with the collective controller feature enabled, compromising confidentiality, integrity, and availability.
Affected Products
- IBM WebSphere Application Server - Liberty 17.0.0.3
- IBM WebSphere Application Server - Liberty versions through 26.0.0.8
- Deployments with the collectiveController-1.0 feature enabled
Discovery Timeline
- 2026-07-28 - CVE-2026-14976 published to NVD
- 2026-07-30 - Last updated in NVD database
Technical Details for CVE-2026-14976
Vulnerability Analysis
CVE-2026-14976 is a remote code execution vulnerability in the collective controller component of IBM WebSphere Application Server - Liberty. The collective controller centralizes management of multiple Liberty servers organized into a collective. When the collectiveController-1.0 feature is enabled, the controller exposes management interfaces that lack proper authentication controls for a critical function. An attacker positioned on the adjacent network can leverage this exposure to execute code within the context of the WebSphere Liberty runtime. The Common Weakness Enumeration classification for this flaw is [CWE-306] Missing Authentication for Critical Function. Exploitation requires user interaction and elevated attack complexity, but no privileges are needed on the target system.
Root Cause
The root cause is the absence of authentication enforcement on a critical management function exposed by the collectiveController-1.0 feature. Management operations that should require verified administrative credentials are reachable without the expected authentication step, permitting attacker-controlled input to reach code execution paths in the controller.
Attack Vector
The attack vector is Adjacent Network, meaning the attacker must reside on the same logical network segment as the target Liberty collective controller. Exploitation also requires user interaction, and the attack complexity is high. When conditions align, the attacker sends crafted requests to the collective controller endpoint and triggers code execution on the server. Refer to the IBM Support Page for vendor-specific technical detail on affected code paths.
Detection Methods for CVE-2026-14976
Indicators of Compromise
- Unexpected outbound network connections originating from Liberty JVM processes hosting the collectiveController-1.0 feature.
- New or modified files in the Liberty server wlp/usr/servers/<serverName>/ directory outside of change windows.
- Unusual child processes spawned by the Liberty Java process, such as shell interpreters or scripting utilities.
Detection Strategies
- Inventory Liberty servers and identify any server.xml configurations that include the collectiveController-1.0 feature.
- Alert on management API requests to collective controller endpoints from hosts not on the approved administrative allowlist.
- Correlate authentication failures and successful management operations to surface requests reaching critical functions without prior authentication.
Monitoring Recommendations
- Enable verbose audit logging on Liberty collective controllers and forward logs to a central SIEM for analysis.
- Monitor process lineage on hosts running WebSphere Liberty to detect unexpected process creation by the Java runtime.
- Track outbound connections from Liberty hosts against known-good baselines to identify command-and-control activity.
How to Mitigate CVE-2026-14976
Immediate Actions Required
- Identify all IBM WebSphere Application Server - Liberty instances in versions 17.0.0.3 through 26.0.0.8 and confirm whether collectiveController-1.0 is enabled.
- Restrict network access to collective controller ports to a dedicated management VLAN accessible only by authorized administrators.
- Apply the fixed version provided by IBM as documented on the IBM Support Page.
Patch Information
IBM has published remediation guidance for CVE-2026-14976 on the IBM Support Page. Administrators should consult this advisory for the specific interim fix or fix pack that addresses the collective controller code path and apply it to every affected Liberty runtime.
Workarounds
- Disable the collectiveController-1.0 feature in server.xml on Liberty servers that do not require collective management.
- Enforce network segmentation so that only trusted management hosts can reach the collective controller endpoints.
- Require TLS client certificate authentication on the management network path to reduce exposure to adjacent-network attackers.
# Configuration example: remove collectiveController-1.0 from server.xml
# Before:
# <featureManager>
# <feature>collectiveController-1.0</feature>
# </featureManager>
#
# After (feature disabled where not required):
# <featureManager>
# </featureManager>
#
# Then restart the Liberty server:
${WLP_HOME}/bin/server stop <serverName>
${WLP_HOME}/bin/server start <serverName>
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
