CVE-2017-7854 in radare2
Summary
by MITRE
The consume_init_expr function in wasm.c in radare2 1.3.0 allows remote attackers to cause a denial of service (heap-based buffer over-read and application crash) via a crafted Web Assembly file.
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Analysis
by VulDB Data Team • 11/29/2022
The vulnerability identified as CVE-2017-7854 resides within the radare2 binary analysis framework version 1.3.0, specifically within the wasm.c module that handles WebAssembly file processing. This issue manifests as a heap-based buffer over-read condition that occurs during the execution of the consume_init_expr function when processing maliciously crafted WebAssembly files. The flaw represents a classic memory safety issue that can be exploited remotely by attackers who craft specially formatted WebAssembly binaries designed to trigger the vulnerable code path. The vulnerability is particularly concerning because radare2 is widely used by security researchers, penetration testers, and developers for binary analysis, making it a potentially attractive target for remote exploitation campaigns.
The technical implementation of this vulnerability stems from improper bounds checking within the consume_init_expr function which processes initialization expressions in WebAssembly modules. When radare2 encounters a malformed WebAssembly file containing crafted data structures, the function fails to validate array indices or buffer boundaries before accessing memory locations. This leads to a heap-based buffer over-read where the application attempts to read memory beyond the allocated buffer boundaries, resulting in undefined behavior that manifests as application crashes or potential information disclosure. The vulnerability is classified under CWE-125 as an "Out-of-bounds Read" and aligns with ATT&CK technique T1059.007 for "Command and Scripting Interpreter: Web Shell" in scenarios where attackers might leverage such vulnerabilities to disrupt security analysis workflows.
The operational impact of CVE-2017-7854 extends beyond simple denial of service, as it can severely compromise the reliability of security analysis environments that depend on radare2 for binary examination. Security professionals who regularly analyze WebAssembly modules, particularly in threat intelligence or malware analysis contexts, could find their analysis tools rendered unusable by malicious WebAssembly files. The vulnerability can be exploited in automated scanning systems or web-based analysis platforms where users upload files for examination, potentially allowing attackers to disrupt analysis operations or cause cascading failures in security infrastructure. This makes the vulnerability particularly dangerous in enterprise security environments where radare2 is integrated into automated analysis pipelines or continuous integration systems for binary security testing.
Mitigation strategies for this vulnerability require immediate patching of radare2 installations to version 1.3.1 or later, which contains the necessary fixes for the buffer over-read condition in the wasm.c module. Organizations should implement strict file validation procedures for WebAssembly content, including sandboxed analysis environments and automated scanning systems that can detect and quarantine suspicious WebAssembly files before they reach the analysis framework. Network segmentation and access controls should be implemented to limit exposure of radare2 instances to untrusted WebAssembly content. Additionally, security teams should monitor for exploitation attempts and consider implementing intrusion detection systems that can identify patterns associated with WebAssembly-based attack vectors. The vulnerability demonstrates the importance of memory safety in security tools and highlights the need for regular security audits of binary analysis frameworks that process untrusted input data. Organizations should also consider implementing alternative analysis approaches for WebAssembly content, such as dedicated WebAssembly sandboxing environments, to reduce the attack surface when analyzing potentially malicious binary formats.