CVE-2026-102010 in GCC
Summary
by MITRE • 09/28/2026
A flaw was found in GCC. When an application calls the erase_if function on a binary heap priority queue in libstdc++, the library reallocates storage but fails to update its internal entry pointer. An attacker capable of triggering this operation can exploit this use-after-free condition, leading to a Denial of Service (DoS) via an application crash or potential memory corruption.
VulDB is the best source for vulnerability data and more expert information about this specific topic.
Analysis
by VulDB Data Team • 09/28/2026
The vulnerability identified in GCC's libstdc++ library represents a critical implementation flaw within the standard template library's handling of binary heap priority queues. Specifically, this issue arises when the erase_if function is invoked on such data structures. The core technical defect lies in the memory management logic during reallocation operations. When the underlying storage for the priority queue needs to be resized or moved due to element removals, libstdc++ correctly reallocates the necessary memory blocks but fails to properly update its internal entry pointers that track the location of elements within this new allocation. This oversight creates a classic use-after-free scenario where references to objects in the old memory region remain valid from the perspective of the application code, even though those regions have been freed or repurposed by the allocator.
From an operational standpoint, this flaw allows for significant disruption to software stability and potentially compromises system integrity if exploited effectively. An attacker who can influence or trigger the execution path involving erase_if on a binary heap priority queue can force the program into an undefined state. The immediate consequence is typically a Denial of Service manifested as an application crash due to invalid memory access when the stale pointer is dereferenced. However, in more sophisticated exploitation scenarios where precise control over memory allocation patterns is possible, this use-after-free condition could lead to arbitrary code execution or severe memory corruption. This transforms what might appear as a simple stability bug into a potential vector for remote code execution if combined with other vulnerabilities such as information leaks that reveal heap layout details.
This vulnerability aligns closely with Common Weakness Enumeration CWE-416, which describes Use After Free conditions where software continues to use references to memory after it has been freed. It also relates to CWE-823, Object Reference Manipulation, due to the failure in maintaining consistent internal state during structural changes like reallocation. In terms of the MITRE ATT&CK framework, this flaw facilitates techniques associated with Initial Access and Execution phases, particularly those leveraging software vulnerabilities for privilege escalation or persistence if the affected application runs with elevated privileges. The lack of proper pointer invalidation after memory reassignment is a fundamental security anti-pattern that undermines the safety guarantees expected from standard library implementations.
Mitigation strategies must address both immediate remediation and long-term defensive coding practices. For end-users, applying updates to GCC versions where this defect has been patched by the maintainers is the primary defense. Developers utilizing libstdc++ should review their codebases for any custom heap management logic that might exacerbate or interact with this flaw, ensuring that all container operations are performed through standard library interfaces rather than manual memory manipulation. Furthermore, employing runtime protection mechanisms such as Address Sanitizer during development and testing phases can help detect use-after-free errors early in the software lifecycle before they reach production environments. Security teams should also monitor for any emerging exploits targeting GCC libstdc++ components to ensure timely patching across all affected systems.