CVE-2007-5666 in Acrobat Reader
Summary
by MITRE
Untrusted search path vulnerability in Adobe Reader and Acrobat 8.1.1 and earlier allows local users to execute arbitrary code via a malicious Security Provider library in the reader s current working directory. NOTE: this issue might be subsumed by CVE-2008-0655.
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Analysis
by VulDB Data Team • 03/16/2021
The vulnerability described in CVE-2007-5666 represents a critical untrusted search path issue affecting Adobe Reader and Acrobat versions 8.1.1 and earlier. This flaw resides in the software's handling of security provider libraries and creates a pathway for local attackers to execute arbitrary code on affected systems. The vulnerability specifically exploits how the application searches for security components, particularly when a malicious library is placed in the current working directory of the reader process. This type of vulnerability falls under the CWE-427 Uncontrolled Search Path Element category, which directly relates to the improper handling of library loading sequences in software applications.
The technical implementation of this vulnerability exploits the order-of-precedence in library loading mechanisms within Adobe's security framework. When Adobe Reader or Acrobat attempts to load a security provider library, it searches through a predetermined list of directories without sufficient validation of the library's authenticity or source. This search path behavior allows an attacker to place a malicious library file in the current working directory where the application is executing, causing the legitimate application to load and execute the attacker-controlled code instead of the intended security provider. The vulnerability demonstrates a classic privilege escalation vector that leverages the trust model inherent in the application's library loading process, enabling local users to gain elevated privileges or execute malicious payloads with the application's privileges.
The operational impact of this vulnerability extends beyond simple code execution, as it provides attackers with a mechanism to bypass security controls and potentially escalate privileges within the target environment. Since the attack requires only local access to the system, it can be particularly dangerous in environments where users have legitimate access to Adobe Reader or Acrobat applications. The vulnerability creates a persistent threat vector that can be exploited by malware authors to establish backdoors, exfiltrate data, or further compromise the system through additional attack vectors. This weakness aligns with the ATT&CK technique T1059 Command and Scripting Interpreter and T1068 Exploitation for Privilege Escalation, as it allows attackers to execute code with elevated privileges and potentially maintain persistence.
Mitigation strategies for this vulnerability involve implementing proper input validation and secure library loading practices within the application. Adobe addressed this issue through patches that modified the library loading behavior to prioritize system directories over the current working directory and implement stricter validation of security provider libraries. Organizations should ensure that all systems running Adobe Reader or Acrobat are updated to versions that include the security patches, while also implementing application whitelisting policies that restrict the execution of untrusted code in critical application directories. Additionally, security configurations should enforce secure search path practices and regularly audit the current working directories of critical applications to prevent malicious library placement. The vulnerability serves as a reminder of the importance of secure coding practices and proper library loading mechanisms, particularly in applications that handle sensitive security functions and require trust in external components.