CVE-2021-43907Network attack vector

Unauthenticated remote code execution

Published Dec 15, 2021 · Updated Aug 4, 2024

Remote code execution in Microsoft Visual Studio Code WSL before 0.63.11 allows remote attackers to execute code through its WSL server. Microsoft identifies the vulnerable locus as the VS Code server running inside the WSL distribution but does not disclose the unsafe operation on network input. No authentication or user interaction is required, and successful exploitation grants code execution with the server process's access.

CVSS severity9.8
Critical
EPSS probability3.79%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Remote code execution in Microsoft Visual Studio Code WSL before 0.63.11 allows remote attackers to execute code through its WSL server. Microsoft identifies the vulnerable locus as the VS Code server running inside the WSL distribution but does not disclose the unsafe operation on network input. No authentication or user interaction is required, and successful exploitation grants code execution with the server process's access.

The record

CVE
CVE-2021-43907
Published
Dec 15, 2021
Updated
Aug 4, 2024
Vendor
Microsoft
Product
Visual Studio Code WSL
Classifications
T1210
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Dec 15, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <0.63.11

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Microsoft · Visual Studio Code WSLversion=0 <0.63.11

Published CVSS scores

9.8Microsoft CorporationCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
10.0NIST NVDAV:N/AC:L/Au:N/C:C/I:C/A:C
9.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1210Exploitation of Remote Services

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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