CVE-2012-2376 in PHP
Summary
by MITRE
Buffer overflow in the com_print_typeinfo function in PHP 5.4.3 and earlier on Windows allows remote attackers to execute arbitrary code via crafted arguments that trigger incorrect handling of COM object VARIANT types, as exploited in the wild in May 2012.
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Analysis
by VulDB Data Team • 12/31/2024
The vulnerability identified as CVE-2012-2376 represents a critical buffer overflow flaw within the PHP scripting language implementation on Windows platforms. This issue specifically affects PHP versions 5.4.3 and earlier, where the com_print_typeinfo function demonstrates improper handling of COM object VARIANT types. The vulnerability stems from insufficient bounds checking when processing crafted input arguments that manipulate COM object metadata, creating conditions where attacker-controlled data can overwrite adjacent memory locations. The flaw occurs within the Windows-specific COM integration layer of PHP, making it particularly dangerous in environments where PHP applications interact with Windows COM components or handle untrusted input from external sources.
The technical exploitation of this vulnerability leverages the inherent characteristics of COM object VARIANT types which can contain different data representations including strings, integers, and pointers. When the com_print_typeinfo function processes these variants, it fails to properly validate the size of incoming data structures, allowing attackers to craft malicious inputs that exceed the allocated buffer space. This improper memory management creates a classic buffer overflow condition that can be leveraged to execute arbitrary code with the privileges of the affected PHP process. The attack vector typically involves supplying specially crafted COM object arguments that trigger the vulnerable code path, potentially leading to remote code execution on the target system.
The operational impact of CVE-2012-2376 extends beyond simple code execution, as it provides attackers with significant control over affected systems. Since the vulnerability affects PHP installations on Windows platforms, it particularly targets web servers running PHP applications that utilize COM components or process external data through COM interfaces. The exploitation in the wild during May 2012 demonstrated that attackers could leverage this flaw to establish persistent access, escalate privileges, and potentially compromise entire server infrastructures. Organizations running vulnerable PHP versions on Windows systems faced immediate risk of unauthorized access to sensitive data, system compromise, and potential lateral movement within network environments. The vulnerability's exploitation often resulted in complete system takeover, making it a severe threat to web application security and server integrity.
Mitigation strategies for CVE-2012-2376 primarily focus on immediate version updates to PHP 5.4.4 or later, which contain patches addressing the buffer overflow in the com_print_typeinfo function. System administrators should prioritize upgrading PHP installations and thoroughly test applications to ensure compatibility with newer versions. Additional protective measures include implementing strict input validation for all COM object interactions, disabling unnecessary COM extensions when not required, and employing network segmentation to limit potential attack surfaces. Organizations should also consider implementing runtime protections such as DEP (Data Execution Prevention) and ASLR (Address Space Layout Randomization) to make exploitation more difficult. The vulnerability aligns with CWE-121, which describes unsafe use of stack-based buffer, and maps to ATT&CK technique T1059.007 for execution through PHP scripts, highlighting the importance of comprehensive security controls including application whitelisting and monitoring for suspicious COM object usage patterns.