CVE-2021-34524Network attack vector

Authenticated remote code execution

Published Aug 12, 2021 · Updated Aug 10, 2026

Remote code execution in Microsoft Dynamics 365 on-premises 9.0 and 9.1 allows remote authenticated users to execute code over the network. Microsoft's public record identifies no affected component or unsafe operation, leaving the code-level mechanism undisclosed. Low-privileged authentication is required; exploitation permits arbitrary code execution and reading or modifying data, with no reported availability impact.

CVSS severity8.1
High
EPSS probability3.59%
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 Dynamics 365 on-premises 9.0 and 9.1 allows remote authenticated users to execute code over the network. Microsoft's public record identifies no affected component or unsafe operation, leaving the code-level mechanism undisclosed. Low-privileged authentication is required; exploitation permits arbitrary code execution and reading or modifying data, with no reported availability impact.

The record

CVE
CVE-2021-34524
Published
Aug 12, 2021
Updated
Aug 10, 2026
Vendor
Microsoft
Product
Microsoft Dynamics 365 (on-premises) version 9.1
Classifications
Unavailable
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 12, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 10, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

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

  1. Affected versionversion=9.0 <9.1.3.11

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Microsoft · Microsoft Dynamics 365 (on-premises) version 9.1version=9.0 <9.1.3.11
Microsoft · Microsoft Dynamics 365 (on-premises) version 9.0version=9.0.0 <9.0.31.7

Published CVSS scores

8.1Microsoft CorporationCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
8.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
6.5NIST NVDAV:N/AC:L/Au:S/C:P/I:P/A:P

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)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

No sourced classifications are available.

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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