CVE-2025-66692: Trust Wallet Core DoS Vulnerability

CVE-2025-66692 Overview

A buffer over-read vulnerability exists in the PublicKey::verify() method of Binance Trust Wallet Core prior to commit 5668c67. This memory safety issue allows remote attackers to cause a Denial of Service (DoS) condition by supplying specially crafted input to the vulnerable function. The vulnerability stems from improper bounds checking when processing cryptographic verification operations, potentially allowing memory reads beyond allocated buffer boundaries.

Critical Impact

Remote attackers can crash Trust Wallet Core applications by exploiting the buffer over-read in cryptographic signature verification, leading to service disruption for cryptocurrency wallet users.

Affected Products

• Binance Trust Wallet Core (versions before commit 5668c67)
• Applications and services integrating vulnerable Trust Wallet Core library versions
• Mobile and desktop cryptocurrency wallet implementations using affected library builds

Discovery Timeline

• 2026-01-20 - CVE CVE-2025-66692 published to NVD
• 2026-01-21 - Last updated in NVD database

Technical Details for CVE-2025-66692

Vulnerability Analysis

This vulnerability is classified as CWE-126 (Buffer Over-read), a memory safety issue that occurs when a program reads data past the end of an allocated buffer. In the context of Trust Wallet Core, the PublicKey::verify() method fails to properly validate input boundaries before performing cryptographic signature verification operations.

When processing malformed or oversized input, the function attempts to read memory beyond the bounds of the input buffer. This out-of-bounds read operation can result in the application crashing due to accessing invalid memory regions, effectively causing a denial of service condition. The network-accessible attack vector means that any service or application exposing Trust Wallet Core's signature verification functionality to external input is potentially vulnerable.

Root Cause

The root cause of this vulnerability lies in insufficient input validation within the PublicKey::verify() method. The function does not adequately verify the size of input data before processing, allowing attackers to supply crafted payloads that trigger reads beyond buffer boundaries. This is a common class of memory safety vulnerability in C++ codebases where manual memory management and pointer arithmetic are employed without proper bounds checking.

Attack Vector

The vulnerability is exploitable over the network without requiring authentication or user interaction. An attacker can exploit this flaw by:

1. Identifying an application or service that uses Trust Wallet Core for cryptographic operations
2. Crafting a malicious payload designed to trigger the buffer over-read condition
3. Sending the crafted input to the target's signature verification endpoint
4. Causing the application to crash when PublicKey::verify() attempts to read beyond buffer boundaries

The attack results in denial of service, disrupting cryptocurrency wallet operations and transaction signing capabilities. A proof-of-concept demonstrating this vulnerability is available in the GitHub Gist PoC.

Detection Methods for CVE-2025-66692

Indicators of Compromise

• Unexpected application crashes or restarts in services utilizing Trust Wallet Core
• Crash dumps or core files indicating memory access violations in the PublicKey::verify() function
• Unusual or malformed cryptographic verification requests in application logs
• Repeated crash events correlating with specific network requests or API calls

Detection Strategies

• Monitor application stability metrics for Trust Wallet Core-dependent services and flag unusual crash patterns
• Implement input validation logging to detect oversized or malformed payloads sent to signature verification endpoints
• Deploy memory sanitizers (AddressSanitizer, MemorySanitizer) in testing environments to detect buffer over-read conditions
• Review network traffic for anomalous patterns targeting cryptocurrency wallet API endpoints

Monitoring Recommendations

• Enable crash reporting and telemetry for all applications using Trust Wallet Core library
• Set up alerting for repeated service restarts or availability degradation in wallet services
• Monitor for known PoC patterns in incoming requests to cryptographic verification APIs
• Implement rate limiting on signature verification endpoints to mitigate potential DoS attempts

How to Mitigate CVE-2025-66692

Immediate Actions Required

• Update Trust Wallet Core to commit 5668c67 or later, which contains the security fix
• Audit all applications and services that integrate Trust Wallet Core library for vulnerable versions
• Implement input validation at the application layer to reject malformed or oversized verification requests
• Consider temporarily disabling exposed signature verification endpoints if immediate patching is not possible

Patch Information

The vulnerability has been addressed in Trust Wallet Core commit 5668c67. Organizations should update their Trust Wallet Core dependency to this commit or any subsequent release. The fix can be reviewed in the GitHub Commit Update.

To update, rebuild applications with the patched version of the library and redeploy affected services.

Workarounds

• Implement application-level input size validation before passing data to PublicKey::verify()
• Deploy a web application firewall (WAF) to filter potentially malicious requests to verification endpoints
• Isolate wallet services in containerized environments with automatic restart policies to minimize DoS impact
• Restrict network access to cryptographic API endpoints to trusted sources only