What is the CVSS score of CVE-2026-21518?

CVE-2026-21518 has a CVSS 3.1 base score of 8.8 (High). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H. EPSS exploitation probability: 0.0%.

Which versions of Github are affected by CVE-2026-21518?

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.. A patch is available.

How to fix or mitigate CVE-2026-21518?

Within 24 hours: Inventory all instances of GitHub Copilot and VS Code across the organization and disable Copilot features until mitigation is confirmed. Within 7 days: Implement network segmentation to restrict Copilot's external communications, review logs for suspicious activity, and communicate interim guidance to development teams. Within 30 days: Monitor vendor advisories closely for patch availability, conduct a security assessment of any potentially compromised repositories, and develop a patching strategy for rapid deployment once available.

Github CVE-2026-21518

HIGH

Command Injection (CWE-77)

2026-02-10 secure@microsoft.com

Github Command Injection AI / ML Visual Studio Code

8.8

CVSS 3.1 · NVD

Severity by source

NVD PRIMARY

8.8 HIGH

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

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

Required

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Lifecycle Timeline

Analysis Generated

Mar 12, 2026 - 22:02 vuln.today

CVE Published

Feb 10, 2026 - 18:16 nvd

HIGH 8.8

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.

AnalysisAI

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.

Technical ContextAI

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.