Description

Improper neutralization of parameter/argument delimiters in Microsoft Edge (Chromium-based) allows an unauthorized attacker to execute code over a network.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "5.4",
  "pubDate": "2026-08-28T20:19:34.280Z",
  "pubdate": "2026-08-28T20:19:34.280Z",
  "executiveSummary": "This vulnerability involves an instance of improper neutralization of parameter and argument delimiters within Microsoft Edge, based on the Chromium engine.\nThe vulnerability allows a remote, unauthorized attacker to trigger arbitrary code execution (ACE) over a network connection.\nBy manipulating specific parameters processed by the browser's command-line handling or internal argument parsing logic, an attacker can escape expected operational boundaries.\nThe scope of impact includes potential full system compromise, as successful exploitation enables the execution of arbitrary instructions in the security context of the affected process.\nThis flaw represents a critical risk to organizational assets using Microsoft Edge, as it does not inherently require local user interaction if chained with other primitives, although network-level access is a primary prerequisite.\nThe vulnerability resides in how the browser interprets and sanitizes input strings intended for internal functions or external system calls, leading to delimiter injection that subverts command syntax integrity.",
  "technicalDetails": "The root cause of this vulnerability is a failure in the input validation logic responsible for sanitizing command-line arguments or parameters passed to the browser's execution environment. In Chromium-based architectures, such as Microsoft Edge, the browser frequently processes complex input strings from various sources, including URI handlers, inter-process communication (IPC) messages, or command-line switches.\nWhen delimiters—such as quotes, escape characters, or specific separator sequences—are not properly neutralized, an attacker can inject additional parameters or malicious instructions into a target function call. This is often described as an argument injection vulnerability where the parser interprets malicious input as a legitimate argument intended by the application developer.\nThe attack flow typically initiates when a remote attacker sends a specifically crafted input package to the browser. This could be delivered via a malicious link, a crafted file association, or an exploitation of an exposed IPC bridge within the network. Upon receipt, the browser's argument-parsing routine fails to treat the injected delimiter as literal data, thereby allowing the attacker to 'break out' of the intended execution context.\nOnce the delimiter is successfully processed, the attacker can force the browser to execute system commands or launch secondary processes with elevated flags or unintended arguments. This effectively bypasses the security constraints designed to prevent the execution of arbitrary binaries or scripts via browser parameters.\nThe vulnerable component is the parameter parsing logic integrated into the Chromium browser engine's core infrastructure. Because this logic is fundamental to how the browser initializes processes and communicates with the underlying OS, the exploit can result in full remote code execution.\nExploitation does not typically require prior authentication, as the browser interface is designed to handle external inputs directly from the network or user-initiated actions. Successful exploitation allows the attacker to transition from network-level interaction to code execution within the browser's process space, which may subsequently be used for lateral movement or data exfiltration, depending on the integrity level of the compromised process."
}