CVE-2022-1240 in radare2
Summary
by MITRE • 04/06/2022
Heap buffer overflow in libr/bin/format/mach0/mach0.c in GitHub repository radareorg/radare2 prior to 5.8.6. If address sanitizer is disabled during the compiling, the program should executes into the `r_str_ncpy` function. Therefore I think it is very likely to be exploitable. For more general description of heap buffer overflow, see [CWE](https://cwe.mitre.org/data/definitions/122.html).
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Analysis
by VulDB Data Team • 04/08/2022
The heap buffer overflow vulnerability identified as CVE-2022-1240 resides within the Mach0 binary format parser of radare2 version 5.8.5 and earlier. This flaw exists in the libr/bin/format/mach0/mach0.c source file where improper bounds checking allows maliciously crafted Mach0 binary files to trigger memory corruption during parsing operations. The vulnerability specifically manifests when the program executes the r_str_ncpy function, which is commonly used for string copying operations within the binary analysis framework. The issue becomes particularly concerning when address sanitizer is disabled during compilation, as this removes crucial runtime protections that would otherwise detect or prevent the buffer overflow condition.
The technical implementation of this vulnerability stems from inadequate input validation when processing Mach0 binary headers and metadata structures. When radare2 attempts to parse malformed Mach0 files, the parsing logic fails to properly validate the size parameters of string fields within the binary format, leading to a situation where data exceeding the allocated heap buffer space gets written. This heap-based memory corruption occurs because the r_str_ncpy function does not perform sufficient bounds checking to prevent writing beyond the intended buffer boundaries. The vulnerability is classified under CWE-122 which specifically addresses heap-based buffer overflow conditions, where an attacker can write data beyond the allocated buffer space in heap memory.
Operationally, this vulnerability presents significant exploitation risks for adversaries seeking to compromise systems running vulnerable versions of radare2. The heap buffer overflow can potentially lead to arbitrary code execution, denial of service conditions, or information disclosure depending on the specific memory layout and exploitation techniques employed. Since radare2 is widely used for reverse engineering, malware analysis, and security research, attackers could craft malicious Mach0 binaries that, when analyzed by vulnerable systems, would trigger the buffer overflow. This creates a dangerous attack surface where legitimate security tools become potential vectors for compromise. The vulnerability's exploitability is heightened when address sanitizer is disabled, removing important runtime protections that would otherwise prevent or detect such memory corruption scenarios.
Mitigation strategies for CVE-2022-1240 should prioritize immediate upgrading to radare2 version 5.8.6 or later, which contains the necessary patches to address the heap buffer overflow in the Mach0 parser. Organizations should also implement defensive measures such as disabling automatic binary analysis of untrusted files, employing sandboxing techniques for binary analysis operations, and ensuring that address sanitizer is enabled during compilation to provide additional runtime protection. The vulnerability aligns with ATT&CK technique T1059.007 which covers command and scripting interpreter usage, as exploitation may involve crafting malicious binary content that triggers the vulnerable parsing logic. Security teams should also monitor for any potential indirect exploitation pathways through automated analysis systems that might process untrusted binary content without proper validation mechanisms in place.