CVE-2021-26434: Microsoft Visual Studio Incorrect Permission Assignment Privilege Escalation Vulnerability

Published Sep 14, 2021
·
Updated

Visual Studio Elevation of Privilege Vulnerability

Other sources

This vulnerability allows local attackers to escalate privileges on affected installations of Microsoft Visual Studio. An attacker must first obtain the ability to execute low-privileged code on the target system in order to exploit this vulnerability. The specific flaw exists within the Visual Studio installer. The issue results from incorrect permissions set on a resource used by the installer. An attacker can leverage this vulnerability to escalate privileges and execute arbitrary code in the context of SYSTEM.

ZDI

Affected Software

8 affected componentsFixes available
Microsoft Visual Studio
Microsoft Visual Studio 2017>=15.0<=15.9
Microsoft Visual Studio 2019>=16.0<=16.11
Microsoft Visual Studio 2019 (includes 16.0 - 16.3)=16.4
16.4.26
Microsoft Visual Studio 2019 (includes 16.0 - 16.8)=16.9
16.9.11
Microsoft Visual Studio 2019 (includes 16.0 – 16.6)=16.7
16.7.19
Microsoft Visual Studio 2019 (includes 16.0 - 16.10)=16.11
16.11.3
Microsoft Visual Studio 2017 (includes 15.0 - 15.8)=15.9
15.9.39

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 16.9.11
  2. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 16.7.19
  3. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 16.4.26
  4. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 15.9.39
  5. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 16.11.3

Event History

Sep 14, 2021
CVE Published
via Microsoft·02:00 PM
Data Sourced
via Microsoft·02:00 PM
DescriptionSeverityWeakness
Data Sourced
via Microsoft·02:00 PM
Affected Software
Updated
via Microsoft·02:00 PM
Description
Sep 15, 2021
CVE Published
via MITRE·11:23 AM
Data Sourced
via MITRE·11:23 AM
DescriptionSeverity
Data Sourced
via NVD·12:15 PM
RemedyDescriptionSeverityWeaknessAffected Software
Sep 16, 2021
Advisory Published
via ZDI·12:00 AM
Data Sourced
via ZDI·12:00 AM
DescriptionSeverityAffected Software

Frequently Asked Questions

1

What is CVE-2021-26434?

CVE-2021-26434 is a vulnerability in Microsoft Visual Studio that allows local attackers to escalate privileges on affected installations.

2

How severe is CVE-2021-26434?

CVE-2021-26434 has a severity rating of 7.8, which is considered high.

3

How can I fix CVE-2021-26434?

To fix CVE-2021-26434, you should update the affected installations of Microsoft Visual Studio to the patched versions.

4

Where can I find more information about CVE-2021-26434?

You can find more information about CVE-2021-26434 on the Microsoft Security Response Center website and the Zero Day Initiative advisories.

Contact

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