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Δ / VULNERABILITY RECORD

CVE-2026-21523.

Source-reported disclosure and enrichment record.

SEVERITY / CVSSHIGH / 8No severity score in this snapshot.
EXPLOITATION STATUSNot listed in the cached KEV catalogThis does not establish absence of exploitation.
RECORD STATUSMicrosoft vendor recordModified Apr 20, 2026

Disclosure summary

Time-of-check time-of-use (toctou) race condition in GitHub Copilot and Visual Studio allows an authorized attacker to execute code over a network.

Source-reported weakness categories

CWE-367

Source-specific records & product guidance

Sources retain their own attribution and scoring. Follow the original record to confirm affected versions, fixed releases, and configuration conditions.

Microsoft Security Updates (CVRF) · 2026-Feb

Open original source · Updated Apr 20, 2026

GitHub Copilot and Visual Studio Code Remote Code Execution Vulnerability

Maximum of vendor-reported product scores; products and fixed builds are associations, not a universal affected-version statement.

Microsoft maximum product score: 8

VendorProduct / associationVersion / bounds
Microsoft update guideMicrosoft Visual Studio Code CoPilot Chat Extension (MSRC status code 3)
Microsoft update guideVisual Studio Code (MSRC status code 3)

Vendor remediation references

Original records & references

PUBLISHED 2026-02-10T03:00:00-05:00
MODIFIED 2026-04-20T03:00:00-04:00
INGESTED 2026-10-08T12:45:18-04:00