CVE-2023-39410: Apache Avro DoS Vulnerability

CVE-2023-39410 Overview

CVE-2023-39410 is an insecure deserialization vulnerability affecting Apache Avro Java SDK. When deserializing untrusted or corrupted data, it is possible for a reader to consume memory beyond the allowed constraints, leading to an out of memory condition on the system. This vulnerability poses a significant denial of service risk to Java applications that process serialized Avro data from untrusted sources.

Critical Impact

Attackers can exploit this vulnerability to cause memory exhaustion and denial of service by sending specially crafted serialized data to applications using vulnerable versions of Apache Avro Java SDK.

Affected Products

• Apache Avro Java SDK up to and including version 1.11.2
• Java applications utilizing Apache Avro for data serialization
• Systems processing untrusted Avro data streams

Discovery Timeline

• September 29, 2023 - CVE-2023-39410 published to NVD
• February 13, 2025 - Last updated in NVD database

Technical Details for CVE-2023-39410

Vulnerability Analysis

This vulnerability is classified under CWE-502 (Deserialization of Untrusted Data). The core issue resides in the deserialization mechanism of the Apache Avro Java SDK, where insufficient validation of incoming data allows a reader to allocate memory without proper bounds checking. When an attacker provides specially crafted or maliciously corrupted serialized data, the deserialization process attempts to allocate excessive memory resources, ultimately exhausting the available heap space.

The vulnerability is particularly concerning in environments where Avro is used for inter-service communication, message queuing, or data pipeline processing where input data may originate from untrusted sources. The network-accessible nature of this attack vector means that any service accepting Avro-serialized data over the network could be targeted.

Root Cause

The root cause lies in the deserialization routines of Apache Avro Java SDK that fail to enforce adequate memory constraints when processing incoming data. The Avro reader does not properly validate or limit the size of data structures being reconstructed during deserialization. This allows an attacker to craft input that triggers excessive memory allocation, bypassing any logical limits that should prevent runaway memory consumption.

Attack Vector

The attack is network-based and requires no authentication or user interaction. An attacker can craft malicious Avro-serialized payloads designed to trigger excessive memory allocation during deserialization. These payloads can be delivered to vulnerable applications through any network interface that accepts Avro data, including REST APIs, message queues, or streaming data pipelines.

The vulnerability manifests when the Avro reader processes untrusted serialized data without proper memory constraints. Attackers can exploit this by sending specially crafted payloads that cause the deserialization process to allocate memory far beyond expected limits. For detailed technical information, refer to the Apache Mailing List Thread and the Openwall OSS-Security Discussion.

Detection Methods for CVE-2023-39410

Indicators of Compromise

• Abnormal memory consumption spikes in Java processes utilizing Apache Avro
• OutOfMemoryError exceptions in application logs related to Avro deserialization operations
• Unusual network traffic patterns with large or malformed Avro payloads targeting application endpoints
• Application crashes or restarts correlated with incoming data deserialization events

Detection Strategies

• Monitor JVM heap memory usage for sudden spikes during Avro deserialization operations
• Implement application-level logging to track deserialization events and payload sizes
• Configure alerting for OutOfMemoryError exceptions in Java applications using Avro
• Use dependency scanning tools to identify Apache Avro versions <=1.11.2 in your codebase

Monitoring Recommendations

• Deploy APM (Application Performance Monitoring) solutions to track memory utilization patterns in Avro-dependent services
• Establish baseline memory consumption metrics and alert on significant deviations
• Implement network traffic analysis to detect anomalous payload sizes destined for Avro-processing endpoints
• Enable verbose garbage collection logging to identify memory pressure patterns

How to Mitigate CVE-2023-39410

Immediate Actions Required

• Upgrade Apache Avro Java SDK to version 1.11.3 or later immediately
• Inventory all applications using Apache Avro and prioritize patching based on exposure to untrusted data
• Implement input validation and size limits on incoming Avro payloads as a defense-in-depth measure
• Consider rate limiting or circuit breakers for services processing external Avro data

Patch Information

Apache has addressed this vulnerability in apache-avro version 1.11.3. Users should update their Maven or Gradle dependencies to reference the patched version. The fix implements proper memory constraint enforcement during deserialization operations. For official patch details, refer to the Apache Mailing List Thread. NetApp customers should also consult the NetApp Security Advisory NTAP-20240621-0006 for additional guidance.

Workarounds

• Implement strict input validation and payload size limits before deserialization
• Deploy network-level protections to filter or throttle suspicious traffic patterns
• Isolate Avro-processing services in containers with strict memory limits to prevent system-wide impact
• Consider using application firewalls or WAF rules to inspect and filter incoming payloads

# Configuration example - Update Maven dependency to patched version
# In pom.xml, update the Avro dependency:
# <dependency>
#     <groupId>org.apache.avro</groupId>
#     <artifactId>avro</artifactId>
#     <version>1.11.3</version>
# </dependency>

# For Gradle, update build.gradle:
# implementation 'org.apache.avro:avro:1.11.3'

# Verify installed version
mvn dependency:tree | grep avro