CVE-2026-58294 in Edge
Summary
by MITRE • 07/04/2026
Use after free in Microsoft Edge (Chromium-based) allows an unauthorized attacker to execute code over a network.
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Analysis
by VulDB Data Team • 07/04/2026
This vulnerability represents a critical use-after-free condition that exists within Microsoft Edge's chromium-based rendering engine, specifically affecting how the browser handles memory management during object lifecycle operations. The flaw occurs when the browser attempts to access memory that has already been freed, creating a scenario where malicious code can manipulate the freed memory location to execute arbitrary instructions. This type of vulnerability falls under the common weakness enumeration CWE-416 which categorizes use-after-free errors as a serious class of memory safety issues that can lead to remote code execution. The vulnerability is particularly dangerous because it can be exploited over a network without requiring any user interaction, making it a prime target for automated attacks. Attackers can craft malicious web pages that trigger the vulnerable code path when Edge renders them, potentially allowing complete system compromise.
The technical exploitation of this vulnerability involves leveraging the browser's memory management system to corrupt heap memory structures and redirect execution flow to attacker-controlled code. When Microsoft Edge processes certain web content containing crafted JavaScript or HTML elements, it triggers a sequence where objects are freed from memory but references to those objects remain in the system. An attacker can manipulate the timing and memory layout to ensure that when the freed memory is reallocated, it contains malicious payload data that gets executed during normal browser operations. This requires precise control over memory allocation patterns and understanding of the browser's internal object management mechanisms.
The operational impact of this vulnerability extends beyond simple code execution, as successful exploitation can lead to full system compromise with elevated privileges. Network-based attackers can deliver malicious content through various vectors including compromised websites, email attachments, or even legitimate web services that are manipulated to serve malicious payloads. The attack surface is particularly broad given Edge's widespread use across enterprise environments and the fact that no user interaction is required for exploitation. This makes the vulnerability especially dangerous in corporate networks where edge browsers are often used as primary web clients. Organizations may experience complete system takeovers, data exfiltration, or persistence mechanisms being established through this attack vector.
Mitigation strategies should focus on immediate patch management and browser hardening measures to reduce exploitability. Microsoft has released security updates that address this specific vulnerability through memory safety improvements in the chromium rendering engine and enhanced heap management controls. Organizations should implement network-based protections such as web application firewalls, content filtering systems, and strict browser security policies that limit access to potentially malicious websites. Additionally, deploying exploit prevention technologies like Address Space Layout Randomization and Data Execution Prevention can make successful exploitation more difficult. Regular security assessments of browser configurations and monitoring for suspicious network activity related to browser exploits should be part of ongoing security operations. This vulnerability demonstrates the critical importance of timely patch management and the need for robust memory safety practices in modern web browsers, aligning with attack techniques documented in the attack tree framework where use-after-free conditions represent common initial access vectors for advanced persistent threats.