HighVulnerability

CVE-2026-21256: GitHub Copilot and Visual Studio command injection over network

Source: NVD(opens in a new tab)
Identifier: CVE-2026-21256
Published: February 10, 2026
Record updated: October 9, 2026

Known exploitation: Not listed in the CISA Known Exploited Vulnerabilities catalog at the last check.
EPSS: 1.2%

Summary

CVE-2026-21256 is an improper neutralization of special elements used in a command, also known as command injection (CWE-77), in GitHub Copilot and Visual Studio. The source states that an unauthorized attacker can execute code over a network. NVD has not yet provided an assessment, and the record was published on 02/10/2026.

Mitigation

The source does not state a fix yet. Check the original advisory for updates.

Details

Scores and exploitation

CVSS score: 8.8(high)
EPSS: 1.2%Estimated probability that this CVE is exploited in the next 30 days, from the FIRST Exploit Prediction Scoring System. Read on November 4, 2026.

Weaknesses and techniques

Weakness (CWE): CWE-77
CWE-94
CWE-77
Attack pattern (CAPEC): CAPEC-242
CAPEC-88

Affected

Vendors: Microsoft

Classification

Attack type: Other
Attack sophistication: Moderate
AI component targeted: Plugin
Impact: Confidentiality,
Integrity,
Availability
Labels: security

How this record was produced

Summaries, mitigations and labels on this page are generated automatically from the source. The linked source is authoritative. The source gives this advisory a description and no title, so the title above is a headline generated from the source text.

Original source: https://nvd.nist.gov/vuln/detail/CVE-2026-21256

First tracked: February 15, 2026 at 08:51 PM ET, from NVD/CVE Database

Classifier: claude-haiku-5-5, prompt v4

Classifier confidence: 85% (self-assessed)

Topics

Coding assistants

Summary

Mitigation

Topics

Related items