CVE-2021-27064

Local code execution via elevated feedback client

Published Apr 13, 2021 · Updated Aug 15, 2025

Code execution in the Visual Studio Installer for Visual Studio 2017 and 2019 allows local users to run code with elevated privileges. The installer launches the Visual Studio Feedback Client while retaining its elevated security context, allowing low-privilege input to reach an elevated process. A local low-privilege account and an installer workflow that starts the feedback client are required; successful exploitation executes code with elevated rights.

CVSS severityUnavailable
Unscored
EPSS probability0.59%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Code execution in the Visual Studio Installer for Visual Studio 2017 and 2019 allows local users to run code with elevated privileges. The installer launches the Visual Studio Feedback Client while retaining its elevated security context, allowing low-privilege input to reach an elevated process. A local low-privilege account and an installer workflow that starts the feedback client are required; successful exploitation executes code with elevated rights.

The record

CVE
CVE-2021-27064
Published
Apr 13, 2021
Updated
Aug 15, 2025
Vendor
Microsoft
Product
Microsoft Visual Studio 2019
Classifications
T1068
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Apr 13, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 15, 2025Record 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=15.0.0 <publication
  2. Affected versionversion=16.0.0 <publication
  3. Affected versionversion=16.0 <publication

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Microsoft · Microsoft Visual Studio 2019version=15.0.0 <publication; version=16.0.0 <publication; version=16.0 <publication
Microsoft · Microsoft Visual Studio 2017version=15.9.0 <publication

Published CVSS scores

No CVSS assessment is available in this record.

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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

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

Weakness, pattern, technique

T1068Exploitation for Privilege Escalation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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