The vulnerability involves an improper limitation of a pathname to a restricted directory, allowing a path traversal flaw in the GitHub Copilot and Visual Studio Code Copilot Chat Extension. An attacker who can access the local environment of the extension can exploit this flaw to bypass a security feature that is intended to restrict file system access. The flaw does not allow remote code execution but can undermine the integrity of the local development environment, potentially allowing read or modification of files outside the intended sandbox.

Microsoft Visual Studio Code Copilot Chat Extension is affected. No specific versions are listed; the issue applies to any instance of the extension that has not been updated to a version containing the fix.

The CVSS score of 8.4 indicates a high severity of the vulnerability. Because the EPSS score is not available, the exploitation likelihood cannot be quantified, and the vulnerability is not listed in the CISA KEV catalog. The attack vector appears to be local, requiring the attacker to be able to run or install the vulnerable extension within a user’s environment. Once the extension is enabled, the path traversal flaw can be triggered by manipulating file paths supplied to the extension, thereby subverting the intended directory restrictions.