CVE-2019-1010025 in C Library
Summary
by MITRE
GNU Libc current is affected by: Mitigation bypass. The impact is: Attacker may guess the heap addresses of pthread_created thread. The component is: glibc.
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Analysis
by VulDB Data Team • 08/05/2024
CVE-2019-1010025 represents a heap address information disclosure vulnerability within GNU Libc that undermines security mitigations designed to protect against heap-based attacks. This vulnerability specifically affects the pthread_create function implementation within glibc, where an attacker can potentially guess or predict heap addresses of threads that have been created through this mechanism. The flaw resides in the memory allocation and management routines that handle thread creation, creating an information disclosure channel that can be exploited to bypass existing security protections such as address space layout randomization and other heap-based mitigations.
The technical implementation of this vulnerability stems from insufficient entropy in the heap address allocation process for newly created pthread objects. When glibc creates new threads using pthread_create, it allocates memory from the heap for thread control blocks and associated structures. The vulnerability occurs because the allocation algorithm does not properly randomize or obscure the memory addresses where these thread structures are placed, allowing an attacker who has access to the system to make educated guesses about thread heap locations. This bypasses the intended security controls that should prevent attackers from easily determining memory layout information.
The operational impact of this vulnerability is significant for systems running affected versions of glibc, particularly in environments where privilege escalation or remote code execution attacks are possible. Attackers can leverage this information disclosure to perform more sophisticated attacks such as heap spraying, return-oriented programming, or other memory corruption exploits that rely on knowing the memory layout of target processes. The ability to guess heap addresses of pthread-created threads undermines the effectiveness of various exploit mitigation techniques and can significantly reduce the complexity of successful exploitation attempts. This vulnerability is particularly concerning in multi-threaded applications where thread management is frequent and predictable.
The vulnerability aligns with CWE-200, which addresses information exposure, and can be categorized under ATT&CK technique T1059 for system information discovery. The flaw represents a bypass of memory protection mechanisms that are fundamental to modern exploit mitigation strategies. Organizations should prioritize updating their glibc implementations to versions that address this specific heap address disclosure issue, as the vulnerability can be exploited without requiring elevated privileges or specialized access to the target system. Security teams should monitor for any exploitation attempts that leverage this information disclosure to predict thread heap locations, as such activities could indicate targeted attacks against systems running vulnerable glibc versions. The mitigation approach primarily involves applying the relevant security patches from the glibc maintainers and ensuring that all systems are updated to versions that properly randomize heap allocations for thread objects.