Github
CVE-2026-21256
HIGH
Severity by source
AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
Lifecycle Timeline
2DescriptionCVE.org
Improper neutralization of special elements used in a command ('command injection') in GitHub Copilot and Visual Studio allows an unauthorized attacker to execute code over a network.
AnalysisAI
Remote code execution in GitHub Copilot and Visual Studio 2022 via command injection allows unauthenticated attackers to execute arbitrary code over the network with user interaction. The vulnerability stems from improper sanitization of special elements in commands, enabling attackers to break out of intended command contexts and inject malicious payloads. No patch is currently available for this high-severity issue affecting both development environments.
Technical ContextAI
Classified as CWE-77 (Command Injection). Affects Visual Studio 2022. Improper neutralization of special elements used in a command ('command injection') in GitHub Copilot and Visual Studio allows an unauthorized attacker to execute code over a network.
RemediationAI
Monitor vendor advisories for a patch. Restrict network access to the affected service where possible.
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Same weakness CWE-77 – Command Injection
View allSame technique Command Injection
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External POC / Exploit Code
Leaving vuln.today