CVE-2024-5971 is a high-severity (CVSS 7.5) CWE-674 vulnerability in io.undertow:undertow-core. A fix is available for io.undertow:undertow-core — see the affected versions and patch details below.
Undertow: response write hangs in case of java 17 tlsv1.3 newsessionticket
Exploitation Status
No confirmed exploitation observed yet
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2024-5971.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2024-5971 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,636 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
io.undertow:undertow-core☕io.undertow:undertow-coreReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Maven packages — download data is not available via public APIs for these ecosystems.
Description
A vulnerability was found in Undertow, where the chunked response hangs after the body was flushed. The response headers and body were sent but the client would continue waiting as Undertow does not send the expected 0\r\n termination of the chunked response. This results in uncontrolled resource consumption, leaving the server side to a denial of service attack. This happens only with Java 17 TLSv1.3 scenarios.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | io.undertow:undertow-core | ≥ 2.3.0.Alpha1&&< 2.3.15.Final | 2.3.15.Finalio.undertow:undertow-core:2.3.15.Final |
| ☕Maven | io.undertow:undertow-core | all versions | 2.2.34.Finalio.undertow:undertow-core:2.2.34.Final |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for io.undertow:undertow-core, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update io.undertow:undertow-core to 2.3.15.Final or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2024-5971 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2024-5971 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2024-5971. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
The identified vulnerability in Undertow, where chunked responses fail to terminate properly under Java 17 with TLSv1.3, represents a significant security concern due to its potential for uncontrolled resource consumption and denial of service (DoS) attacks. This issue arises from Undertow's mishandling of chunked…
| Product | Fixed in | Advisory |
|---|---|---|
| Red Hat build of Apache Camel 3.20.7 for Spring Boot | undertow | RHSA-2024:6883 |
| Red Hat build of Apache Camel 4.4.1 for Spring Boot 3.2 | undertow | RHSA-2024:4884 |
| Red Hat build of Apache Camel 4.4.2 for Spring Boot | see advisory | RHSA-2024:6508 |
| Red Hat JBoss Enterprise Application Platform | io.undertow/undertow-core:2.2.33.SP1-redhat-00001 | RHSA-2024:5147 |
| Red Hat JBoss Enterprise Application Platform 7.4 for RHEL 8 | eap7-undertow-0:2.2.33-1.SP1_redhat_00001.1.el8eap | RHSA-2024:5144 |
| Red Hat JBoss Enterprise Application Platform 7.4 for RHEL 9 | eap7-undertow-0:2.2.33-1.SP1_redhat_00001.1.el9eap | RHSA-2024:5145 |
| Red Hat JBoss Enterprise Application Platform 7.4 on RHEL 7 | eap7-undertow-0:2.2.33-1.SP1_redhat_00001.1.el7eap | RHSA-2024:5143 |
| Red Hat JBoss Enterprise Application Platform 8 | undertow-core | RHSA-2024:4392 |
Frequently Asked Questions
Is CVE-2024-5971 in your dependencies?
O3 Security finds CVE-2024-5971 across Maven dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.