# CVE-2026-42833: Microsoft Dynamics 365 code injection

Source: https://junglewise.ai/threats/cve-2026-42833-microsoft-dynamics-365-code-injection  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-05-12. Updated: 2026-06-01  
License: CC BY 4.0 with a link back

CVE-2026-42833 · Severity: critical · CVSS 9.1 · Published 2026-05-12

Microsoft Dynamics 365 (on-premises) is a business application suite used for customer relationship management and enterprise resource planning. A critical vulnerability allows an authorized user with high-level permissions to inject and execute malicious code on the server. This could lead to a complete takeover of the application environment, unauthorized access to sensitive business data, and disruption of corporate operations.

Technologies: [Microsoft Dynamics 365 (on-premises)](https://junglewise.ai/threats/technologies/dynamics-365-on-premises), [Microsoft Dynamics 365](https://junglewise.ai/threats/technologies/dynamics-365). Vendors: [Microsoft](https://junglewise.ai/threats/vendors/microsoft).

## Quick answers

**Is CVE-2026-42833 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-42833 being exploited in the wild.

**How severe is CVE-2026-42833?** Critical severity, with a CVSS score of 9.1, published 12 May 2026.

**Which products and versions are affected?** Microsoft Dynamics 365 (on-premises) 9.1 up to (excluding) 9.1.45.11.

**Is there a fix for CVE-2026-42833?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-42833 attacked?** It is attacked over the network, in a network appliance.

**Am I affected by CVE-2026-42833?** Check whether you run Microsoft Dynamics 365 (on-premises) or Microsoft Dynamics 365 at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

A code injection vulnerability exists in Microsoft Dynamics 365 (on-premises) due to improper control of code generation. An attacker with high-level administrative privileges (PR:H) can exploit this flaw over a network without any user interaction. Successful exploitation allows for arbitrary code execution with the potential to escape the application's security scope (Scope: Changed). The vulnerability is tracked as CWE-94 (Code Injection) and was previously associated with CWE-250 (Execution with Unnecessary Privileges). Microsoft has released security updates to address this issue in version 9.1.45.11 and later.

## Affected products

- Microsoft Dynamics 365 (on-premises) 9.1 up to (excluding) 9.1.45.11

## Timeline

- 2026-05-12: disclosed
- 2026-05-12: advisory: Initial advisory published by Microsoft
- 2026-06-01: other: Vulnerability description updated to specify code injection

## References

- [https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-42833](https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-42833)

## Related threats

- [Microsoft Dynamics 365 XML external entity injection](https://junglewise.ai/threats/cve-2026-122196-improper-restriction-of-xml-external-entity-reference-in)
- [Microsoft Dynamics 365 code injection in code generation](https://junglewise.ai/threats/cve-2026-77908-microsoft-dynamics-365-code-injection-in-code-generation)
- [Microsoft Dynamics 365 deserialization of untrusted data](https://junglewise.ai/threats/cve-2026-65772-microsoft-dynamics-365-deserialization-of-untrusted-data)
- [Microsoft Dynamics 365 sensitive information disclosure](https://junglewise.ai/threats/cve-2026-66301-microsoft-dynamics-365-sensitive-information-disclosure)
- [Microsoft Dynamics 365 deserialization of untrusted data in on-premises](https://junglewise.ai/threats/cve-2026-65815-microsoft-dynamics-365-deserialization-of-untrusted-data-in-on)