Github
CVE-2026-21518
HIGH
Attack ChainAIDerived
Hypothetical attack flow derived from CVE metadata – not a confirmed exploit chain
-
AccessCraft malicious code snippet
-
ExploitTrick user into accepting Copilot suggestion
-
ExecutionExecute injected command in local environment
-
ImpactCompromise system with user 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 | User interaction required: victim must accept malicious GitHub Copilot code suggestion in Visual Studio Code. Affects default installations with Copilot extension enabled and command execution capabilities. |
| Impact | CVSS 8.8 (HIGH). Attack vector: Network. Complexity: Low. Privileges required: None. User interaction: Required. Exploitation no authentication required. Exploitable via remote/network. |
| Exploit ScenarioDerived | A remote attacker without authentication could exploit this vulnerability to compromise the affected system. |
Get an e-mail when this CVE is exploited, patched or re-scored. Free account.
Alert meAnalysisAIv1 – Mar 12, 2026
GitHub Copilot and Visual Studio Code are vulnerable to command injection attacks that allow unauthenticated attackers to bypass security features over the network through improper neutralization of special command elements. The vulnerability requires user interaction to exploit and could enable attackers to execute arbitrary commands with high impact on confidentiality, integrity, and availability. No patch is currently available for this issue.
Earlier versions of this analysis (1)
Improper neutralization of special elements used in a command ('command injection') in GitHub Copilot and Visual Studio Code allows an unauthorized attacker to bypass a security feature over a network. [CVSS 8.8 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 Code. Improper neutralization of special elements used in a command ('command injection') in GitHub Copilot and Visual Studio Code allows an unauthorized attacker to bypass a security feature over a network.
Know when Github gets its next vulnerability
- Watch products and get an email when something new is published
- Check this CVE against your own stack and servers
- Exploit and PoC references, threat intelligence from 22 sources
No credit card · 7-day full trial
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
DescriptionCVE.org
Improper neutralization of special elements used in a command ('command injection') in GitHub Copilot and Visual Studio Code allows an unauthorized attacker to bypass a security feature over a network.
Zero Day Initiative Advisories
Executive ViewAI
A command injection vulnerability in GitHub Copilot and Visual Studio Code (CVSS 8.8) allows attackers to bypass security controls over the network without requiring user authentication. This affects developers across the organization who use these tools, potentially enabling unauthorized code execution and intellectual property theft through compromised development environments.
Disable GitHub Copilot extension in VS Code until patch release; restrict network egress from development workstations to Copilot services via firewall/proxy rules; isolate development VLANs from production networks; require code review and static analysis scanning for all Copilot-generated code; monitor process execution logs on developer machines for anomalous command patterns; consider alternative code completion tools without known vulnerabilities.
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
Supply chain vulnerability in Eclipse Theia GitHub Actions workflow. The preview.yml workflow uses pull_request_target w
Supply chain attack vector in OpenLIT GitHub Actions workflows. The pull_request_target trigger with checkout enables ma
Eigent multi-agent workflow CI pipeline (ci.yml) uses pull_request_target with checkout of untrusted PR code, enabling a
An unsafe reflection vulnerability was identified in GitHub Enterprise Server that could lead to reflection injection. R
cmark-gfm is GitHub's extended version of the C reference implementation of CommonMark. Rated critical severity (CVSS 9.
An improper verification of cryptographic signature vulnerability was identified in GitHub Enterprise Server that allowe
Unauthenticated infrastructure overwrite in Hoppscotch API development ecosystem before 2026.2.0. Attackers can overwrit
A exposure of sensitive information vulnerability exists in Jenkins GitHub Plugin 1.29.1 and earlier in GitHubTokenCrede
OneUptime versions prior to 10.0.19 allow unauthenticated attackers to hijack GitHub App integrations across projects by
PolarLearn versions 0-PRERELEASE-15 and earlier lack proper state parameter validation in OAuth 2.0 authentication, enab
Path traversal in esm.sh CDN prior to version 0.0.0-20260116051925-c62ab83c589e allows unauthenticated remote attackers
actions/artifact is the GitHub ToolKit for developing GitHub Actions. Rated high severity (CVSS 7.5), this vulnerability
GitHub PoC
Exploit-DB