CVE-2024-2410: Google Protobuf Use-After-Free Vulnerability

CVE-2024-2410 Overview

CVE-2024-2410 is a critical Use-After-Free vulnerability in the Google Protocol Buffers (protobuf) C++ implementation. The vulnerability exists in the JsonToBinaryStream() function, which is used to parse JSON data from a stream. When input is broken up into separate chunks in a specific way, the parser will attempt to read bytes from a memory chunk that has already been freed, leading to potentially severe security consequences.

Critical Impact

This Use-After-Free vulnerability in Google Protocol Buffers can allow remote attackers to execute arbitrary code, access sensitive information, or cause denial of service by exploiting improper memory handling during JSON stream parsing.

Affected Products

• Google Protobuf (versions prior to v25.0)
• Applications using the Protocol Buffers C++ implementation with JsonToBinaryStream() functionality
• Services processing chunked JSON data through protobuf parsing

Discovery Timeline

• 2024-05-03 - CVE CVE-2024-2410 published to NVD
• 2025-07-22 - Last updated in NVD database

Technical Details for CVE-2024-2410

Vulnerability Analysis

This vulnerability is classified as CWE-416 (Use After Free), a memory corruption vulnerability that occurs when a program continues to use a pointer after the memory it references has been freed. In the context of the JsonToBinaryStream() function, the issue manifests during the processing of chunked JSON input streams.

The Protocol Buffers library is a widely-used serialization framework developed by Google, employed across countless applications for efficient data exchange. The JsonToBinaryStream() function provides a mechanism to convert JSON-formatted data into the binary protobuf format directly from a stream, which is particularly useful when handling large payloads or network data that arrives in segments.

The vulnerability arises from improper memory lifecycle management when the JSON parser processes input data that has been divided into discrete chunks. Under specific chunking conditions, the parser maintains references to memory buffers that have already been deallocated, subsequently attempting to read from these dangling pointers.

Root Cause

The root cause of this vulnerability lies in the memory management logic within the JsonToBinaryStream() function's chunked input handling. When JSON data arrives in multiple segments, the parser must manage buffer lifecycles carefully to ensure that no references persist to freed memory regions. In vulnerable versions, certain chunk boundary conditions cause the parser to retain stale pointers to previously processed (and subsequently freed) buffer segments.

This represents a classic Use-After-Free pattern where the temporal relationship between memory deallocation and subsequent access is violated. The parser's internal state incorrectly assumes buffer validity, leading to access of deallocated heap memory when specific chunking patterns are encountered.

Attack Vector

The attack vector for CVE-2024-2410 is network-based, requiring no authentication or user interaction. An attacker can exploit this vulnerability by sending specially crafted JSON data to an application that processes it using the vulnerable JsonToBinaryStream() function.

The exploitation scenario involves:

1. Identifying a target application that uses Google Protocol Buffers to parse JSON input streams
2. Crafting malicious JSON payload with specific chunk boundaries designed to trigger the Use-After-Free condition
3. Sending the crafted input to the target service, causing the parser to access freed memory
4. Depending on heap layout and exploitation techniques, potentially achieving arbitrary code execution, information disclosure, or service disruption

The vulnerability can be triggered over any protocol that delivers JSON data to a protobuf-based parser, including HTTP APIs, gRPC services, or custom network protocols leveraging protobuf serialization.

Detection Methods for CVE-2024-2410

Indicators of Compromise

• Abnormal application crashes or segmentation faults in services using Protocol Buffers JSON parsing
• Memory corruption errors logged by applications processing JSON-to-protobuf conversions
• Unexpected heap memory access patterns detected by memory sanitizers (ASan, MSan)
• Unusual network traffic patterns with fragmented JSON payloads targeting protobuf endpoints

Detection Strategies

• Deploy memory sanitizers (AddressSanitizer, MemorySanitizer) in development and staging environments to detect Use-After-Free conditions
• Implement application-level monitoring for parsing errors and exceptions in protobuf JSON conversion routines
• Use intrusion detection systems to identify anomalous JSON payload patterns with unusual chunking characteristics
• Monitor for application instability patterns that may indicate memory corruption exploitation attempts

Monitoring Recommendations

• Enable verbose logging for protobuf parsing operations to capture potential exploitation attempts
• Implement heap integrity checking in production environments where feasible
• Configure crash reporting systems to capture and analyze memory corruption events
• Monitor memory allocation patterns for services utilizing JsonToBinaryStream() functionality

How to Mitigate CVE-2024-2410

Immediate Actions Required

• Upgrade Google Protocol Buffers to version 25.0 or later immediately
• Inventory all applications and services using the protobuf C++ library with JSON parsing capabilities
• Prioritize patching for internet-facing services that accept JSON input processed by protobuf
• Implement input validation and rate limiting as temporary defense-in-depth measures

Patch Information

Google has addressed this vulnerability in Protocol Buffers version 25.0. The fix corrects the memory management logic in the JsonToBinaryStream() function to properly handle buffer lifecycles during chunked input processing. Organizations should update to protobuf v25.0 or later to remediate this vulnerability.

For environments where immediate patching is not feasible, consider implementing additional network-level controls to restrict access to services that process JSON through Protocol Buffers parsing.

Workarounds

• If upgrading is not immediately possible, consider disabling JSON parsing functionality in favor of native protobuf binary format where applicable
• Implement network segmentation to limit exposure of vulnerable services to trusted networks only
• Deploy Web Application Firewalls (WAF) or API gateways to inspect and potentially block suspicious chunked JSON payloads
• Consider implementing custom input preprocessing to aggregate chunked JSON data before passing to protobuf parser

# Configuration example - Update protobuf dependency
# For CMake-based projects:
# Update CMakeLists.txt to require protobuf >= 25.0
find_package(Protobuf 25.0 REQUIRED)

# For Bazel-based projects:
# Update WORKSPACE to use protobuf v25.0+
# git_repository(
#     name = "com_google_protobuf",
#     remote = "https://github.com/protocolbuffers/protobuf.git",
#     tag = "v25.0",
# )