Github
CVE-2026-21257
HIGH
Attack ChainAIDerived
Hypothetical attack flow derived from CVE metadata – not a confirmed exploit chain
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AccessAuthenticated user receives crafted prompt
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ExploitCopilot processes malicious command injection
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ExecutionExecutes privileged system command
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ImpactAttacker gains elevated privileges
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A05:2025 - Injection
ASVS 5.0
V1 - Encoding and Sanitization Command injection prevention
MITRE ATT&CK
1 technique across 1 tactic: Execution The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. |
| Exploitation Conditions | Requires authenticated user with IDE access to Visual Studio or GitHub Copilot. User interaction needed to process attacker-controlled prompt containing specially crafted command injection payload. Limited to environments where Copilot integrations can execute system commands with elevated privileges. |
| Impact | CVSS 8.0 (HIGH). Attack vector: Network. Complexity: Low. Privileges required: Low. User interaction: Required. Exploitable via remote/network. |
| Exploit ScenarioDerived | A remote attacker could exploit this vulnerability to compromise the affected system. |
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Alert meAnalysisAIv1 – Mar 12, 2026
GitHub Copilot and Visual Studio 2022 contain a command injection vulnerability that allows authenticated users to execute arbitrary commands through improper sanitization of special elements. An attacker with valid credentials can leverage user interaction to escalate privileges and gain elevated access across the network. No patch is currently available for this vulnerability.
Earlier versions of this analysis (1)
Improper neutralization of special elements used in a command ('command injection') in GitHub Copilot and Visual Studio allows an authorized attacker to elevate privileges over a network. [CVSS 8.0 HIGH]
RemediationAI
Monitor vendor advisories for a patch. Restrict network access to the affected service where possible.
Affected Packages
Source: OSV (Open Source Vulnerabilities)
Affects your stack
Affects 2 packages in microsoft
Checking this CVE against your own stacks and servers is part of the Basic plan and up.
Technical ContextAI · show details
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 authorized attacker to elevate privileges over a network.
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- Exploit and PoC references, threat intelligence from 22 sources
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Severity by source
AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
DescriptionCVE.org
Improper neutralization of special elements used in a command ('command injection') in GitHub Copilot and Visual Studio allows an authorized attacker to elevate privileges over a network.
Executive ViewAI
A command injection vulnerability (CVE-2026-21257) in GitHub Copilot and Visual Studio allows authorized users to escalate privileges across network-connected systems. This poses a significant risk to organizations using these development tools, particularly those with privileged developers or shared development environments, as attackers could gain elevated system access.
Disable GitHub Copilot functionality in Visual Studio until patch availability; implement network segmentation to restrict developer machine lateral movement; enforce principle of least privilege on developer accounts; monitor command execution logs from Visual Studio processes for anomalous activity; restrict administrative privileges on development workstations; implement application whitelisting on affected systems; require code review for all Copilot-generated code before execution.
Threat Intelligence Overview
NVD
CVE.org
EPSS
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
OS command injection occurs when an application passes unsanitized user input directly into system shell commands.
Affected Products (CPE)CVE.org
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GitHub PoC
Exploit-DB