CVE-2012-2676 in Hoard
Summary
by MITRE
Multiple integer overflows in the (1) malloc and (2) calloc functions in Hoard before 3.9 make it easier for context-dependent attackers to perform memory-related attacks such as buffer overflows on implementing code via a large size value, which causes less memory to be allocated than expected.
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Analysis
by VulDB Data Team • 02/19/2019
The vulnerability identified as CVE-2012-2676 represents a critical memory management flaw within the Hoard memory allocator library version 3.8 and earlier. This issue stems from integer overflow conditions that occur during the allocation process, specifically affecting both malloc and calloc functions. The flaw creates a scenario where attackers can manipulate memory allocation behavior by providing large size values that, when processed through the vulnerable functions, result in insufficient memory being allocated compared to what the calling code expects. This fundamental discrepancy between allocated and expected memory creates exploitable conditions that can be leveraged for various memory corruption attacks.
The technical implementation of this vulnerability involves the manipulation of integer arithmetic within the memory allocation routines. When large size parameters are passed to the malloc or calloc functions in Hoard, the integer overflow causes the calculated memory requirements to wrap around to smaller values. This occurs because the allocator performs arithmetic operations on size parameters without proper validation or overflow checking. The resulting behavior means that instead of allocating the requested amount of memory, the system allocates significantly less memory than anticipated, creating conditions where subsequent memory operations can overwrite adjacent memory regions. This vulnerability falls under the CWE-190 category of Integer Overflow or Wraparound, which is classified as a common weakness in software development practices.
The operational impact of CVE-2012-2676 extends beyond simple memory allocation failures, as it creates a foundation for more sophisticated memory corruption attacks. Attackers can exploit this vulnerability to perform buffer overflow conditions, heap corruption, and potentially achieve arbitrary code execution within the context of applications using the vulnerable Hoard allocator. The context-dependent nature of this vulnerability means that exploitation requires specific conditions and knowledge of the target application's memory layout, but the underlying flaw makes such attacks more feasible than they would be otherwise. The vulnerability particularly affects systems where Hoard is used as a memory allocator for applications that handle untrusted input or perform dynamic memory allocation based on user-supplied data sizes. This issue aligns with ATT&CK technique T1055 for process injection and T1070 for indicator removal, as attackers can leverage memory corruption to establish persistent access or evade detection mechanisms.
The mitigation strategies for CVE-2012-2676 require immediate action to upgrade to Hoard version 3.9 or later, where the integer overflow conditions have been addressed through proper input validation and arithmetic overflow checking. System administrators should also implement additional safeguards such as address space layout randomization, stack canaries, and heap metadata protection to reduce the effectiveness of potential exploitation attempts. The vulnerability demonstrates the critical importance of proper integer arithmetic validation in memory management systems and serves as a reminder of the need for comprehensive testing of edge cases in allocator implementations. Organizations using Hoard should conduct thorough security assessments of their applications to identify potential exploitation vectors and implement proper memory allocation validation techniques to prevent similar vulnerabilities from manifesting in other components of their software stack.