CVE-2018-17825 in AdPlug
Summary
by MITRE
An issue was discovered in AdPlug 2.3.1. There are several double-free vulnerabilities in the CEmuopl class in emuopl.cpp because of a destructor's two OPLDestroy calls, each of which frees TL_TABLE, SIN_TABLE, AMS_TABLE, and VIB_TABLE.
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Analysis
by VulDB Data Team • 05/19/2023
The vulnerability identified as CVE-2018-17825 represents a critical double-free error within the AdPlug 2.3.1 multimedia library, specifically affecting the CEmuopl class implementation in emuopl.cpp. This flaw demonstrates a classic memory management issue that can lead to severe security implications when exploited in vulnerable applications. The vulnerability stems from improper destructor implementation where the OPLDestroy method is invoked twice, creating a scenario where the same memory regions are freed multiple times during object destruction. The affected memory tables include TL_TABLE, SIN_TABLE, AMS_TABLE, and VIB_TABLE, which are essential components for audio synthesis within the OPL (OPL2/OPL3) emulation framework used by various retro gaming and music playback applications.
The technical nature of this vulnerability places it squarely within CWE-415, which defines double-free conditions as a common memory corruption flaw occurring when a program attempts to free the same memory block twice. This specific implementation error in the CEmuopl class constructor and destructor cycle creates an exploitable condition where an attacker could potentially manipulate the memory state to achieve arbitrary code execution or system instability. The flaw manifests when the destructor calls OPLDestroy twice, with each invocation attempting to free the same memory regions, leading to undefined behavior and potential memory corruption that could be leveraged by malicious actors.
The operational impact of this vulnerability extends beyond simple memory corruption, as it affects any application that relies on AdPlug 2.3.1 for audio playback, particularly those handling untrusted input files such as music modules or game soundtracks. Applications using the library may experience crashes, data corruption, or potentially more severe exploitation scenarios when processing specially crafted audio files that trigger the double-free condition. The vulnerability's exploitation potential aligns with ATT&CK technique T1059.007, which covers the use of command and scripting interpreters, as the memory corruption could enable attackers to manipulate application behavior and potentially gain unauthorized access to system resources.
Mitigation strategies for this vulnerability require immediate patching of the AdPlug library to version 2.3.2 or later, which contains the corrected destructor implementation that prevents the double OPLDestroy calls. Organizations should conduct comprehensive vulnerability assessments to identify all systems utilizing the affected library and implement proper input validation for audio files to prevent exploitation. Additionally, implementing memory safety measures such as address sanitizer instrumentation and regular security testing can help detect similar issues in other components of the application stack. The fix addresses the root cause by ensuring proper single invocation of memory cleanup operations, thereby preventing the double-free condition that could otherwise lead to denial of service or more sophisticated exploitation attempts.