CVE-2026-41605: Apache Thrift Integer Overflow Vulnerability

CVE-2026-41605 Overview

An Integer Overflow or Wraparound vulnerability has been identified in Apache Thrift, a widely-used software framework for scalable cross-language services development. This vulnerability (CWE-190) affects all versions of Apache Thrift prior to 0.23.0 and can be exploited remotely without requiring authentication or user interaction.

Integer overflow vulnerabilities occur when arithmetic operations produce values that exceed the maximum size of the integer data type, causing the value to "wrap around" to unexpected results. In the context of Apache Thrift, this can lead to memory corruption, unexpected application behavior, or potential security bypasses.

Critical Impact

This network-exploitable integer overflow vulnerability in Apache Thrift can potentially compromise confidentiality, integrity, and availability of affected systems without requiring authentication.

Affected Products

• Apache Thrift versions prior to 0.23.0
• Applications and services built using vulnerable Apache Thrift libraries
• Microservices and distributed systems utilizing Apache Thrift for cross-language RPC communication

Discovery Timeline

• April 28, 2026 - CVE-2026-41605 published to NVD
• April 28, 2026 - Last updated in NVD database

Technical Details for CVE-2026-41605

Vulnerability Analysis

The integer overflow vulnerability in Apache Thrift stems from improper handling of arithmetic operations on integer values within the framework's serialization and deserialization routines. When processing specially crafted data, arithmetic operations can exceed the maximum representable value for the integer type, causing the value to wrap around to a small or negative number.

This vulnerability is accessible via network attack vectors without requiring privileges or user interaction. Successful exploitation can result in partial impacts to system confidentiality, integrity, and availability, potentially allowing attackers to read sensitive information, modify data, or cause service disruptions.

Apache Thrift is commonly used in enterprise environments for building scalable cross-language services, making this vulnerability particularly concerning for organizations relying on Thrift-based microservices architectures.

Root Cause

The root cause of this vulnerability is improper validation of integer values before arithmetic operations are performed. When the framework processes input data that causes integer calculations to exceed the maximum value for the data type, the result wraps around according to two's complement arithmetic. This can lead to:

• Buffer size miscalculations resulting in undersized memory allocations
• Incorrect loop bounds leading to out-of-bounds memory access
• Logic errors in security-critical code paths
• Unexpected application state that can be leveraged for further exploitation

The vulnerability is classified under CWE-190 (Integer Overflow or Wraparound), which describes scenarios where an integer value is incremented to a value too large to store in the associated representation, leading to wrapping and unexpected behavior.

Attack Vector

The vulnerability can be exploited remotely over the network without requiring authentication or user interaction. An attacker can craft malicious Thrift protocol messages containing specially constructed integer values designed to trigger the overflow condition.

When the vulnerable Apache Thrift library processes these malicious messages, the integer overflow occurs during deserialization or internal calculations, potentially leading to memory corruption or application crashes. The attack can be performed against any network-exposed service utilizing a vulnerable version of Apache Thrift.

Exploitation typically involves sending specially crafted RPC requests to Thrift services with integer fields containing values near the maximum representable value, causing subsequent arithmetic operations to overflow.

Detection Methods for CVE-2026-41605

Indicators of Compromise

• Unexpected crashes or restarts of services using Apache Thrift
• Anomalous memory consumption patterns in Thrift-based applications
• Unusual network traffic patterns with malformed Thrift protocol messages
• Application logs showing serialization/deserialization errors or integer-related exceptions

Detection Strategies

• Implement application-layer monitoring for Thrift services to detect malformed protocol messages
• Deploy network intrusion detection systems (IDS) with rules for detecting anomalous Thrift traffic patterns
• Enable verbose logging in Thrift services to capture deserialization errors and unusual input values
• Utilize software composition analysis (SCA) tools to identify applications using vulnerable Apache Thrift versions

Monitoring Recommendations

• Monitor Thrift service endpoints for unusual request patterns or high error rates
• Configure alerts for application crashes or unexpected restarts in Thrift-based services
• Track memory utilization metrics for anomalies that may indicate exploitation attempts
• Review system logs for evidence of buffer-related errors or memory access violations

How to Mitigate CVE-2026-41605

Immediate Actions Required

• Upgrade Apache Thrift to version 0.23.0 or later immediately
• Inventory all applications and services using Apache Thrift to identify vulnerable deployments
• Implement network segmentation to limit exposure of Thrift services to trusted networks only
• Enable input validation and rate limiting at network boundaries for Thrift traffic

Patch Information

Apache has released version 0.23.0 to address this vulnerability. Users should upgrade to this version or later to remediate the integer overflow issue. The fix includes proper validation of integer values before arithmetic operations to prevent overflow conditions.

For detailed patch information, refer to the Apache Mailing List Thread. Additional technical details are available in the Openwall OSS-Security Update.

Workarounds

• Implement network-level access controls to restrict Thrift service access to trusted clients only
• Deploy web application firewalls (WAF) or API gateways with custom rules to filter potentially malicious Thrift requests
• Consider containerizing Thrift services with resource limits to contain potential exploitation impact
• Implement input validation at the application layer to reject requests with suspicious integer values

# Configuration example - Verify Apache Thrift version
# Check the version of Apache Thrift in your project dependencies

# For Maven-based projects, check pom.xml:
grep -r "thrift" pom.xml | grep version

# For Gradle-based projects:
grep -r "thrift" build.gradle

# Ensure the version is 0.23.0 or higher
# Update dependency to remediate:
# <dependency>
#     <groupId>org.apache.thrift</groupId>
#     <artifactId>libthrift</artifactId>
#     <version>0.23.0</version>
# </dependency>