CVE-2020-0899

Local System file overwrite via updater permission handling

Published Apr 15, 2020 · Updated Aug 4, 2024

Improper permission handling in Microsoft Visual Studio 2017 and 2019 allows local users to overwrite arbitrary files as Local System. Microsoft has disclosed only that the updater service mishandles file permissions; no file path, function, or permission transition is public. A low-privileged local account is required, and successful exploitation changes file integrity without reported data disclosure or service interruption.

CVSS severity5.5
Medium
EPSS probability0.81%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper permission handling in Microsoft Visual Studio 2017 and 2019 allows local users to overwrite arbitrary files as Local System. Microsoft has disclosed only that the updater service mishandles file permissions; no file path, function, or permission transition is public. A low-privileged local account is required, and successful exploitation changes file integrity without reported data disclosure or service interruption.

The record

CVE
CVE-2020-0899
Published
Apr 15, 2020
Updated
Aug 4, 2024
Vendor
Microsoft
Product
Microsoft Visual Studio 2019
Classifications
T1068
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Apr 15, 2020CVE 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=16.0
  2. Affected versionversion=unspecified

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Microsoft · Microsoft Visual Studio 2019version=16.0; version=unspecified
Microsoft · Microsoft Visual Studio 2017version=unspecified

Published CVSS scores

3.6NIST NVDAV:L/AC:L/Au:N/C:N/I:P/A:P
5.5NIST NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N

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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