# CVE-2021-34484: Microsoft Windows User Profile Service Privilege Escalation Vulnerability

Source: https://junglewise.ai/threats/cve-2021-34484-microsoft-windows-user-profile-service-privilege-escalation  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2022-03-31. Updated: 2026-05-10  
License: CC BY 4.0 with a link back

CVE-2021-34484 · Severity: critical · CVSS 7.8 · Exploited in the wild · Published 2022-03-31

The Microsoft Windows User Profile Service contains an elevation of privilege vulnerability that allows a local attacker to gain SYSTEM privileges. The vulnerability has been observed being exploited in the wild and is included in CISA's Known Exploited Vulnerabilities catalog.

Technologies: [Microsoft Windows](https://junglewise.ai/threats/technologies/windows). Vendors: [Microsoft](https://junglewise.ai/threats/vendors/microsoft).

## Quick answers

**Is CVE-2021-34484 exploited in the wild?** Yes. CVE-2021-34484 is known to be exploited in the wild, first recorded on 31 March 2022. Treat it as urgent.

**How severe is CVE-2021-34484?** Critical severity, with a CVSS score of 7.8, published 31 March 2022.

**Which products and versions are affected?** Microsoft Windows 10 up to (excluding) 10.0.10240.19022; Microsoft Windows 7 Service Pack 1; Microsoft Windows 8.1; Microsoft Windows Server 2008 Service Pack 2; and 3 more.

**Is there a fix for CVE-2021-34484?** 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-2021-34484 attacked?** It is attacked with local access, in an operating system.

**Am I affected by CVE-2021-34484?** Check whether you run Microsoft Windows. 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.

## Affected products

- Microsoft Windows 10 up to (excluding) 10.0.10240.19022
- Microsoft Windows 7 Service Pack 1
- Microsoft Windows 8.1
- Microsoft Windows Server 2008 Service Pack 2
- Microsoft Windows Server 2012
- Microsoft Windows Server 2016 up to (excluding) 10.0.14393.4583
- Microsoft Windows Server 2019 up to (excluding) 10.0.17763.2114

## Timeline

- 2021-08-23: disclosed: Initial analysis by NIST and CVSS assignment.
- 2022-03-31: kev added: Added to CISA Known Exploited Vulnerabilities Catalog.
- 2022-03-31: advisory: NVD publication date.

## Related threats

- [Windows BitLocker heap buffer overflow with physical attack](https://junglewise.ai/threats/cve-2026-97015-heap-based-buffer-overflow-in-windows-bitlocker-allows-an)
- [Microsoft Windows Shell type confusion privilege elevation](https://junglewise.ai/threats/cve-2026-97013-access-of-resource-using-incompatible-type-type-confusion-in)
- [Microsoft Windows VMSwitch out-of-bounds read privilege escalation](https://junglewise.ai/threats/cve-2026-97002-out-of-bounds-read-in-windows-vmswitch-allows-an-authorized)
- [Microsoft Windows USM Communication Manager null pointer dereference](https://junglewise.ai/threats/cve-2026-97000-null-pointer-dereference-in-windows-usm-communication-manager)
- [Microsoft Windows Winsock use after free privilege escalation](https://junglewise.ai/threats/cve-2026-96994-use-after-free-in-winsock-allows-an-authorized-attacker-to)