Summary
A vulnerability was found in Undertow. This issue requires enabling the learning-push handler in the server's config, which is disabled by default, leaving the maxAge config in the handler unconfigured. The default is -1, which makes the handler vulnerable. If someone overwrites that config, the server is not subject to the attack. The attacker needs to be able to reach the server with a normal HTTP request.
Impact
CVE-2024-3653 has a CVSS score of 5.3 (Medium). The vector is network-reachable, no privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (2.3.15.Final, 2.2.34.Final); upgrading removes the vulnerable code path.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
Remediation advice
io.undertow:undertow-core to 2.3.15.Final or later; io.undertow:undertow-core to 2.2.34.Final or later
Kodem Kai can prioritize this vulnerability in your dependency tree and generate a fix recommendation.
Frequently Asked Questions
- What is CVE-2024-3653? CVE-2024-3653 is a medium-severity security vulnerability in io.undertow:undertow-core (maven), affecting versions >= 2.3.0.Alpha1, < 2.3.15.Final. It is fixed in 2.3.15.Final, 2.2.34.Final.
- How severe is CVE-2024-3653? CVE-2024-3653 has a CVSS score of 5.3 (Medium). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
- Which versions of io.undertow:undertow-core are affected by CVE-2024-3653? io.undertow:undertow-core (maven) versions >= 2.3.0.Alpha1, < 2.3.15.Final is affected.
- Is there a fix for CVE-2024-3653? Yes. CVE-2024-3653 is fixed in 2.3.15.Final, 2.2.34.Final. Upgrade to this version or later.
- Is CVE-2024-3653 exploitable, and should I be worried? Whether CVE-2024-3653 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2024-3653 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix CVE-2024-3653?
- Upgrade
io.undertow:undertow-coreto 2.3.15.Final or later - Upgrade
io.undertow:undertow-coreto 2.2.34.Final or later
- Upgrade