External risk intelligence

IBM WebSphere Application Server SSRF Vulnerability with SIP Container Enabled

CVE advisorySeverity: CRITICAL (CVSS 9.4)

CVE-2026-14529

IBM WebSphere Application Server is a widely deployed enterprise application server typically used to host public-facing web applications, APIs, and business services, making the underlying server infrastructure frequently reachable from the internet.

Missing Authentication

Halo Surface Signal: 4 out of 5 — likely to be public-facing.

External exposure likelihood

Horizon Alert

Summary of the vulnerability and why it matters

A critical vulnerability in IBM WebSphere Application Server could allow an unauthenticated attacker to conduct server-side request forgery, potentially leading to unauthorized access to internal resources and data. This issue arises when a specific feature within the SIP container is enabled, making the affected systems a potential target for malicious activity.

Allows attackers to trick servers into unintended requests.
Affects widely deployed enterprise application servers.
Confirm relevance and exposure to sensitive systems.

Attack Path

How an attacker could exploit the issue

An attacker could exploit this vulnerability by sending a specially crafted request to a vulnerable WebSphere Application Server instance that has the SIP container feature enabled. This could allow the attacker to make the server issue requests to arbitrary internal or external network locations.

Server is reachable from the network.
SIP container feature is enabled.
Attacker forces server to make requests.

Live Threat

Current exploitation, exposure, and threat context

When the SIP container feature is enabled in IBM WebSphere Application Server, a server-side request forgery vulnerability could allow an attacker to trigger unintended requests from the server to arbitrary internal or external resources. This could potentially expose internal network structures or sensitive system information when user-supplied data is not properly validated.

Internal network details.
Unvalidated user input.
Information disclosure.

Operational Fix

Recommended remediation, mitigation, and detection steps

This vulnerability in IBM WebSphere Application Server, specifically when the SIP container feature is enabled, likely impacts platform or infrastructure teams responsible for the application server's configuration and security. The first practical step is to inventory all instances of WebSphere Application Server, determine if the SIP container feature is active, and identify which of these systems are externally accessible or host critical business functions. Subsequently, asset owners and the responsible teams should be identified to plan remediation based on the assessed risk.

Identify affected WebSphere instances and active SIP features.
Verify external reachability and business criticality.
Engage platform owners for remediation planning.

Supplementary metadata

CVSS vector

Validate whether this threat affects your internet-facing exposure.

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Frequently asked questions

What is IBM WebSphere Application Server?

IBM WebSphere is a robust enterprise platform designed to build, deploy, and run Java-based applications, APIs, and business services. It acts as the underlying infrastructure that manages the execution and security of large-scale web services, often serving as a central hub for business-critical data and communication flows in corporate environments.

What does Server-Side Request Forgery mean for CVE-2026-14529?

This vulnerability is classified as CWE-306, which relates to missing authentication for critical functions. In this context, it allows an unauthenticated user to trick the server into making unauthorized requests to internal or external resources on its behalf. Because the server trusts the requests it generates internally, this flaw allows attackers to bypass typical security controls and potentially interact with restricted network segments or sensitive local services.

How is this SSRF vulnerability triggered?

The flaw is triggered by sending a specially crafted request to an instance where the SIP container feature (sipServlet-1.1) is active. The vulnerability does not exist if this specific SIP container feature is disabled, as the underlying request handling path that leads to the forgery is not engaged. Simply running WebSphere is not enough; the specific functional feature must be enabled for the server to be susceptible.

Do I need to worry about this CVE if my server is internal?

Halo Surface Signal indicates that because IBM WebSphere is often used for public-facing applications, many instances are reachable from the internet, increasing the likelihood of risk. However, even if your instance is internal, it may still be vulnerable to attackers who have gained a foothold on your local network. You should prioritize assessing systems that are internet-facing first, then evaluate the risk to internal applications that process untrusted user input.

What should I do first to address CVE-2026-14529?

Begin by creating an inventory of your WebSphere Application Server instances to determine where they are deployed. Next, audit your configurations to identify which servers have the SIP container feature (sipServlet-1.1) enabled. Once you have identified these specific assets, coordinate with your infrastructure and platform teams to evaluate their network accessibility and business criticality to determine the urgency of your remediation efforts.

References

www.ibm.com/support/pages/node/7281721

Written by Nicholas Merritt

Nicholas Merritt is VP of Security Solutions at Halo Security. With more than 25 years across application security, vulnerability prioritization, and offensive security, he helps teams translate threat data into practical exposure validation and remediation focus. He authors Halo Threat Intelligence CVE advisories using Halo Surface Signal and H/A/L/O context to prioritize internet-facing risk.