CVE-2024-21085 Overview
CVE-2024-21085 is a denial of service vulnerability in the Concurrency component of Oracle Java SE and Oracle GraalVM Enterprise Edition. This vulnerability allows an unauthenticated attacker with network access via multiple protocols to cause a partial denial of service condition in affected Java deployments. The vulnerability can be exploited through APIs in the Concurrency component, including through web services that supply data to these APIs, as well as through sandboxed Java Web Start applications and Java applets that load and run untrusted code.
Critical Impact
Successful exploitation can result in unauthorized ability to cause a partial denial of service (partial DoS) of Oracle Java SE and Oracle GraalVM Enterprise Edition, potentially disrupting the availability of Java-based applications and services.
Affected Products
- Oracle JDK 1.8.0 Update 401, 11.0.22
- Oracle JRE 1.8.0 Update 401, 11.0.22
- Oracle GraalVM Enterprise Edition 20.3.13, 21.3.9
- NetApp Active IQ Unified Manager (VMware vSphere, Windows)
- NetApp Data Infrastructure Insights Acquisition Unit
- NetApp Data Infrastructure Insights Storage Workload Security Agent
- NetApp OnCommand Insight
- NetApp OnCommand Workflow Automation
- Debian Linux 10.0
Discovery Timeline
- April 16, 2024 - CVE-2024-21085 published to NVD
- May 21, 2025 - Last updated in NVD database
Technical Details for CVE-2024-21085
Vulnerability Analysis
This vulnerability resides in the Concurrency component of Oracle Java SE and Oracle GraalVM Enterprise Edition. The flaw is difficult to exploit, requiring the attacker to navigate complex conditions to achieve successful exploitation. However, once exploited, it can disrupt the availability of Java-based services by inducing a partial denial of service state.
The vulnerability is particularly concerning because it affects multiple deployment scenarios. It can be triggered through web services that supply data to the affected Concurrency APIs, making it relevant for server-side Java applications. Additionally, client-side deployments running sandboxed Java Web Start applications or Java applets that load untrusted code from the internet are also vulnerable. In these sandboxed scenarios, applications rely on the Java sandbox for security, but this vulnerability allows bypass of those protections to affect availability.
Root Cause
The root cause of CVE-2024-21085 stems from improper handling within the Java Concurrency component. While Oracle has not disclosed specific technical details about the underlying flaw, the vulnerability affects the thread management and concurrent processing mechanisms in Java. The issue allows network-accessible exploitation that can degrade service availability without requiring authentication or user interaction.
Attack Vector
The attack vector for CVE-2024-21085 is network-based, allowing remote unauthenticated attackers to target vulnerable Java installations. The attack requires high complexity, meaning specific conditions must be met for successful exploitation. The attacker must craft requests that interact with the vulnerable Concurrency APIs, either directly through network protocols or indirectly through web services that forward data to these APIs.
In client-side scenarios, the attacker could host malicious content that, when loaded by a sandboxed Java applet or Web Start application, triggers the vulnerability. The vulnerability does not impact confidentiality or integrity but can degrade application availability.
Detection Methods for CVE-2024-21085
Indicators of Compromise
- Unusual resource consumption patterns in Java applications, particularly related to thread management and concurrent operations
- Application performance degradation or partial service interruptions in Java-based web services
- Unexpected behavior in Java applet or Web Start application execution
- Anomalous network traffic patterns targeting Java application endpoints
Detection Strategies
- Monitor Java application logs for exceptions or errors related to concurrency operations and thread management
- Implement application performance monitoring (APM) to detect degraded responsiveness in Java services
- Deploy network intrusion detection systems (IDS) to identify suspicious traffic patterns targeting Java-based endpoints
- Review Java process metrics for abnormal thread counts or CPU utilization patterns
Monitoring Recommendations
- Enable verbose logging for Java applications to capture detailed concurrency-related events
- Configure alerting thresholds for Java heap usage, thread pool exhaustion, and garbage collection anomalies
- Establish baseline performance metrics for Java applications to detect deviations indicative of DoS attempts
- Monitor for repeated failed connections or requests that may indicate exploitation attempts
How to Mitigate CVE-2024-21085
Immediate Actions Required
- Update Oracle Java SE to the latest patched version beyond 8u401 and 11.0.22
- Upgrade Oracle GraalVM Enterprise Edition beyond versions 20.3.13 and 21.3.9
- Review and update NetApp products according to the NetApp Security Advisory
- Apply Debian security updates as described in the Debian LTS Announcement
Patch Information
Oracle has released security patches addressing this vulnerability as part of the April 2024 Critical Patch Update. Organizations should apply the patches available through the Oracle Security Alert. NetApp has also released advisory NTAP-20240426-0004 addressing affected NetApp products. Debian Linux users should apply the security updates announced for Debian 10.0.
Workarounds
- Restrict network access to Java application endpoints using firewall rules and network segmentation
- Disable Java Web Start and Java applets in browser configurations if not required for business operations
- Implement rate limiting on web services that interact with Java Concurrency APIs
- Consider deploying a Web Application Firewall (WAF) to filter potentially malicious requests targeting Java endpoints
# Example: Restrict Java application network access using iptables
# Limit connections to Java application port (example: 8080)
iptables -A INPUT -p tcp --dport 8080 -m connlimit --connlimit-above 100 -j REJECT
iptables -A INPUT -p tcp --dport 8080 -m state --state NEW -m recent --set
iptables -A INPUT -p tcp --dport 8080 -m state --state NEW -m recent --update --seconds 60 --hitcount 30 -j DROP
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
