CVE-2025-30754 Overview
CVE-2025-30754 is a security vulnerability affecting the Java Secure Socket Extension (JSSE) component within Oracle Java SE, Oracle GraalVM for JDK, and Oracle GraalVM Enterprise Edition. This flaw enables an unauthenticated attacker with network access via TLS to potentially compromise affected Java deployments, resulting in unauthorized data modification and read access to sensitive information.
The vulnerability is particularly relevant for client-side Java deployments that execute untrusted code within sandboxed environments, such as Java Web Start applications and Java applets. Server-side deployments that only run administrator-installed trusted code are not affected by this vulnerability.
Critical Impact
Successful exploitation allows unauthorized modification of data and read access to sensitive information in Java deployments running untrusted code via TLS connections.
Affected Products
- Oracle Java SE: 8u451, 8u451-perf, 11.0.27, 17.0.15, 21.0.7, 24.0.1
- Oracle GraalVM for JDK: 17.0.15, 21.0.7, 24.0.1
- Oracle GraalVM Enterprise Edition: 21.3.14
Discovery Timeline
- July 15, 2025 - CVE-2025-30754 published to NVD
- November 3, 2025 - Last updated in NVD database
Technical Details for CVE-2025-30754
Vulnerability Analysis
This vulnerability resides in the JSSE component, which provides the SSL/TLS implementation for Java applications. The flaw represents an Improper Access Control (CWE-284) weakness that can be exploited remotely over the network via TLS connections.
The vulnerability requires high attack complexity, meaning successful exploitation depends on specific conditions being met. While no user interaction or authentication is required to exploit this flaw, the attacker must have network access to the target system's TLS interface.
The impact is limited to confidentiality and integrity breaches without affecting system availability. Attackers can potentially read a subset of accessible data and perform unauthorized updates, insertions, or deletions to some data accessible through the affected Java products.
Root Cause
The root cause is classified as CWE-284 (Improper Access Control), indicating that the JSSE component fails to properly restrict access to resources or operations. This weakness in the TLS implementation allows network attackers to bypass expected security controls within sandboxed Java environments.
The vulnerability specifically affects deployments that rely on the Java sandbox for security when executing untrusted code from external sources such as the internet.
Attack Vector
The attack vector is network-based, requiring the attacker to have TLS connectivity to the target Java deployment. The vulnerability mechanism involves exploiting the JSSE component's improper access control during TLS communication.
The attack scenario involves:
- An attacker establishes a TLS connection to a vulnerable Java deployment running untrusted sandboxed code
- The attacker leverages the improper access control flaw in the JSSE component
- Upon successful exploitation, the attacker gains unauthorized read access to a subset of data and the ability to modify, insert, or delete accessible data
For detailed technical information, refer to the Oracle Security Alert July 2025.
Detection Methods for CVE-2025-30754
Indicators of Compromise
- Anomalous TLS connection patterns to Java applications, particularly from external sources
- Unexpected data access or modification events in applications using the affected JSSE component
- Unusual network traffic patterns during TLS handshakes with Java-based services
- Log entries indicating unauthorized data operations in sandboxed Java environments
Detection Strategies
- Monitor Java application logs for suspicious TLS-related activities and connection anomalies
- Implement network-level detection for malformed or suspicious TLS traffic targeting Java services
- Deploy endpoint detection solutions to identify exploitation attempts against Java runtimes
- Audit data access patterns in applications using JSSE to detect unauthorized operations
Monitoring Recommendations
- Enable detailed logging for JSSE and TLS operations in Java applications
- Configure alerts for unusual data modification or access events in sandboxed Java deployments
- Monitor for connections from untrusted sources to Java Web Start applications or applets
- Track Java runtime versions across the environment to identify unpatched instances
How to Mitigate CVE-2025-30754
Immediate Actions Required
- Update Oracle Java SE, GraalVM for JDK, and GraalVM Enterprise Edition to the latest patched versions
- Inventory all systems running affected Java versions (8u451, 11.0.27, 17.0.15, 21.0.7, 24.0.1)
- Restrict network access to Java deployments running untrusted code where patching is not immediately possible
- Disable Java Web Start and applet functionality if not required in your environment
Patch Information
Oracle has released security patches addressing CVE-2025-30754 as part of the July 2025 Critical Patch Update (CPU). Administrators should update to the latest Java SE, GraalVM for JDK, and GraalVM Enterprise Edition releases.
Patch resources:
Workarounds
- Restrict Java deployments to only execute trusted, administrator-installed code
- Implement network segmentation to limit TLS access to vulnerable Java applications
- Disable sandboxed Java applet and Web Start functionality if not essential for business operations
- Apply strict firewall rules to control network access to systems running affected Java versions
# Check current Java version
java -version
# Verify JSSE security provider configuration
keytool -list -keystore $JAVA_HOME/lib/security/cacerts
# Restrict Java applet/Web Start functionality via deployment properties
echo "deployment.webjava.enabled=false" >> ~/.java/deployment/deployment.properties
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
