CVE-2026-77493 in Windows
Summary
by MITRE • 09/09/2026
Double free in Microsoft Graphics Component allows an unauthorized attacker to execute code over a network.
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Analysis
by VulDB Data Team • 09/09/2026
The vulnerability described involves a critical memory management error within the Microsoft Graphics Component, specifically classified as a double-free condition. This type of flaw occurs when a program attempts to deallocate or release a block of memory that has already been freed by a previous operation. In the context of graphics processing and rendering engines, such errors are particularly dangerous because these components often handle complex data structures involving buffers for images, textures, and display outputs. When an attacker can trigger this double-free scenario through crafted input sent over a network, they exploit the underlying memory allocator's state corruption to gain unauthorized control over system execution flow.
From a technical perspective, the core issue lies in the improper handling of pointer references after deallocation. Once memory is freed, the pointer should ideally be nullified or removed from active tracking lists. However, if the application retains a reference to this now-invalid memory address and subsequently attempts to free it again, the heap metadata becomes corrupted. This corruption can lead to arbitrary write primitives during subsequent allocation requests, allowing an attacker to overwrite critical function pointers or return addresses on the stack. By carefully crafting network packets that trigger specific rendering paths within the graphics component, a remote adversary can manipulate these memory structures to achieve code execution with the privileges of the affected process, which often includes system-level access depending on how the application is invoked.
The operational impact of this vulnerability is severe due to its potential for remote code execution without user interaction in certain configurations. An attacker does not need physical access or local account credentials; they only require network connectivity to deliver the malicious payload. This could involve tricking a victim into viewing a specially crafted image file, visiting a compromised website that utilizes WebGL or similar graphics APIs, or interacting with any application that relies on the vulnerable Microsoft Graphics Component for rendering content. Successful exploitation results in full compromise of the affected system, enabling data theft, installation of malware, establishment of persistent backdoors, and lateral movement within an enterprise network.
This vulnerability aligns closely with Common Weakness Enumeration (CWE) category CWE-415, which defines Double Free as a weakness where memory is freed more than once. Furthermore, in the context of the MITRE ATT&CK framework, this flaw facilitates techniques related to Initial Access via Spearphishing Attachment or Drive-by Compromise if delivered through web-based vectors, and Execution via Arbitrary Code Execution following successful exploitation of the application logic. The lack of proper bounds checking and state validation in memory management routines is a classic indicator of insufficient input validation leading to exploitable conditions.
Mitigation strategies must focus on both immediate remediation and long-term architectural improvements. Organizations should immediately apply vendor-provided security patches that address this specific double-free condition within the Microsoft Graphics Component, ensuring all systems are updated to versions where the memory management logic has been corrected. Developers reviewing similar codebases should implement strict pointer hygiene practices, such as setting pointers to null after freeing them and utilizing static analysis tools designed to detect memory safety violations during the software development lifecycle. Additionally, deploying network intrusion detection systems with signatures capable of identifying anomalous traffic patterns associated with heap exploitation attempts can provide an additional layer of defense against active attacks targeting this vulnerability.