CVE-2026-21523 json
GitHub Copilot and Visual Studio Code Remote Code Execution Vulnerability
published 2026-02-10 8 mo ago modified 2026-08-19 2 mo ago also EUVD-2026-7345
- cvss
- 8.0
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.8%
- EPSS 0.8% chance of exploitation in 30 days, percentile 55%
- public exploits
- 0
- none known
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.
Patch / fix
- Microsoft Microsoft Visual Studio Code CoPilot Chat Extension 0.37.1
- Microsoft Visual Studio Code 1.110.1
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- total
- Assessed
- 8 mo ago
Exploit prediction
0.76% chance of exploitation in the next 30 days, higher than 55% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 8.0 | CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C |
| CNA | 3.1 | 8.0 | CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H |
Affected products
- Microsoft Microsoft Visual Studio Code CoPilot Chat Extension
- Microsoft Visual Studio Code
Classification
- Weakness
-
- CWE-367 Time-of-check Time-of-use (TOCTOU) Race Condition
References
-
msrc.microsoft.com
/update-guide/vulnerability/CVE-2026-21523
vendor-advisory, patch
Sources
- CVE List CVE-2026-21523
- NVD CVE-2026-21523
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