CVE-2025-30753: Oracle WebLogic Server DOS Vulnerability

CVE-2025-30753 Overview

CVE-2025-30753 is a Denial of Service vulnerability in the Core component of Oracle WebLogic Server, part of Oracle Fusion Middleware. This flaw allows a low-privileged attacker with network access via HTTP to cause a complete denial of service condition, resulting in a hang or frequently repeatable crash of the affected WebLogic Server instance. The vulnerability is classified as easily exploitable, requiring minimal attacker sophistication to trigger service disruption.

Critical Impact

Successful exploitation enables attackers to completely disrupt Oracle WebLogic Server availability, causing service outages that can impact critical business applications and middleware infrastructure.

Affected Products

• Oracle WebLogic Server 12.2.1.4.0
• Oracle WebLogic Server 14.1.1.0.0
• Oracle WebLogic Server 14.1.2.0.0

Discovery Timeline

• July 15, 2025 - CVE-2025-30753 published to NVD
• July 25, 2025 - Last updated in NVD database

Technical Details for CVE-2025-30753

Vulnerability Analysis

This vulnerability resides in the Core component of Oracle WebLogic Server and falls under CWE-400 (Uncontrolled Resource Consumption). The flaw enables an authenticated attacker with low-level privileges to trigger resource exhaustion conditions through network-based HTTP requests. The attack does not require user interaction and operates within an unchanged scope, meaning the impact is confined to the vulnerable WebLogic Server component itself.

The vulnerability exclusively affects availability—there is no impact on confidentiality or integrity of data processed by the server. However, the complete denial of service capability makes this a significant concern for organizations relying on WebLogic Server for critical middleware operations, as it can lead to application downtime and business disruption.

Root Cause

The root cause is attributed to improper resource management within the Core component of Oracle WebLogic Server (CWE-400). The server fails to adequately limit or control resource allocation when processing certain HTTP requests, allowing an attacker to consume server resources excessively. This uncontrolled resource consumption leads to server hangs or crashes, effectively denying service to legitimate users.

Attack Vector

The attack vector is network-based, requiring the attacker to have HTTP access to the vulnerable WebLogic Server instance. The attacker must possess low-level privileges (authenticated access) to exploit this vulnerability. The attack complexity is low, meaning no special conditions or sophisticated techniques are required beyond basic network connectivity and valid credentials.

An attacker can craft malicious HTTP requests designed to trigger the resource exhaustion condition in the Core component. When the server processes these requests, it fails to properly manage resource allocation, leading to a complete denial of service. The attack can be repeated frequently, allowing persistent disruption of server availability.

Detection Methods for CVE-2025-30753

Indicators of Compromise

• Unexpected WebLogic Server crashes or hangs without apparent system-level issues
• Elevated HTTP request volumes from specific authenticated users or IP addresses
• Abnormal resource consumption patterns (CPU, memory, thread pool exhaustion) on WebLogic Server instances
• Recurring service restarts or failovers in WebLogic managed server clusters

Detection Strategies

• Monitor WebLogic Server access logs for unusual patterns of HTTP requests, particularly from low-privileged accounts
• Implement application performance monitoring (APM) to detect sudden resource exhaustion events
• Configure alerting for WebLogic Server health metrics including thread pool utilization and request queue depths
• Deploy network-based intrusion detection to identify potential DoS attack patterns targeting WebLogic endpoints

Monitoring Recommendations

• Enable detailed logging in WebLogic Server diagnostic framework to capture request processing anomalies
• Establish baseline metrics for normal server resource utilization to identify deviations indicative of exploitation
• Implement real-time monitoring of WebLogic Server availability with automated alerting for service disruptions
• Review authentication logs to identify potentially compromised low-privileged accounts being used for attack attempts

How to Mitigate CVE-2025-30753

Immediate Actions Required

• Apply the security patch from Oracle's July 2025 Critical Patch Update immediately
• Restrict network access to WebLogic Server administrative and application interfaces to trusted networks only
• Review and audit low-privileged user accounts with HTTP access to WebLogic Server
• Implement rate limiting on HTTP endpoints exposed by affected WebLogic Server instances

Patch Information

Oracle has addressed this vulnerability in the July 2025 Critical Patch Update. Organizations should apply the relevant patches for their WebLogic Server versions (12.2.1.4.0, 14.1.1.0.0, or 14.1.2.0.0) as documented in the Oracle Security Alert July 2025. The patch addresses the uncontrolled resource consumption issue in the Core component, preventing the denial of service condition.

Workarounds

• Implement Web Application Firewall (WAF) rules to detect and block suspicious HTTP request patterns targeting WebLogic Server
• Configure load balancers to implement connection rate limiting and request throttling for WebLogic endpoints
• Enable WebLogic Server work manager constraints to limit resource consumption per user or request type
• Segment WebLogic Server infrastructure to isolate critical instances from potentially compromised network zones

# Example WebLogic Server resource constraint configuration
# Add to config.xml within the relevant server configuration
# This limits concurrent requests to help mitigate resource exhaustion

# Navigate to WebLogic domain directory
cd $DOMAIN_HOME/config

# Backup existing configuration
cp config.xml config.xml.backup

# Consider implementing work manager constraints via WebLogic Console:
# 1. Navigate to Environment > Work Managers
# 2. Create new Work Manager with max-threads-constraint
# 3. Associate with affected applications
# 4. Restart managed servers to apply changes