TOCTOU race condition RCE in GitHub Copilot and Visual Studio Code
Information currently not available in the provided content beyond the high-level classification: CVE-2026-21523 is a time-of-check time-of-use (TOCTOU) race condition affecting GitHub Copilot and Visual Studio Code/Visual Studio, which can allow an authorized attacker to execute code over a network (CVSS v3.1: AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H). No vulnerable function/module, precise attack flow, or technical root-cause details are provided in the supplied material.
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Recent activity
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A remote code execution vulnerability affecting GitHub Copilot integration in Visual Studio Code.
A remote code execution vulnerability affecting GitHub Copilot and Visual Studio Code (also referenced in the table as GitHub Copilot and Visual Studio).
A remote code execution vulnerability affecting GitHub Copilot and Visual Studio Code (no additional details provided in the content).
A TOCTOU (race condition) vulnerability affecting GitHub Copilot and Visual Studio that can allow an authorized attacker to achieve network-based code execution.
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