# CVE-2026-83971: Microsoft Windows Biometric Service heap buffer overflow

Source: https://junglewise.ai/threats/cve-2026-83971-microsoft-windows-biometric-service-heap-buffer-overflow  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-08. Updated: 2026-09-26  
License: CC BY 4.0 with a link back

CVE-2026-83971 · Severity: high · CVSS 7.8 · Published 2026-09-08

Windows Biometric Service is a system component that manages fingerprint and facial recognition authentication on Windows computers. A heap buffer overflow vulnerability in this service allows a user with local access to execute arbitrary code with elevated system privileges, potentially leading to complete compromise of the affected computer.

Technologies: [Microsoft Windows Biometric Service](https://junglewise.ai/threats/technologies/windows-biometric-service). Vendors: [Microsoft](https://junglewise.ai/threats/vendors/microsoft).

## Quick answers

**Is CVE-2026-83971 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-83971 being exploited in the wild.

**How severe is CVE-2026-83971?** High severity, with a CVSS score of 7.8, published 8 September 2026.

**Which products and versions are affected?** Microsoft Windows Biometric Service <UNKNOWN>.

**Is there a fix for CVE-2026-83971?** 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-2026-83971 attacked?** It is attacked with local access.

**Am I affected by CVE-2026-83971?** Check whether you run Microsoft Windows Biometric Service 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 heap-based buffer overflow exists in the Windows Biometric Service, a core Windows component responsible for processing biometric authentication data. The vulnerability requires an authenticated attacker with local access to trigger the overflow condition. Exploitation allows arbitrary code execution with privileges higher than the attacker's current user context, enabling privilege escalation. The attack vector is local-only and requires prior authentication or interactive access to the system. A patch has been released by Microsoft as part of their security update process.

## Affected products

- Microsoft Windows Biometric Service <UNKNOWN>

## Timeline

- 2026-09-08: disclosed

## References

- [https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-83971](https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-83971)

## Related threats

- [Microsoft Windows Biometric Service heap buffer overflow](https://junglewise.ai/threats/cve-2026-83988-microsoft-windows-biometric-service-heap-buffer-overflow)
- [Microsoft Windows Biometric Service heap buffer overflow privilege escalation](https://junglewise.ai/threats/cve-2026-83987-microsoft-windows-biometric-service-heap-buffer-overflow)
- [Microsoft Windows Biometric Service heap buffer overflow](https://junglewise.ai/threats/cve-2026-83985-microsoft-windows-biometric-service-heap-buffer-overflow)
- [Microsoft Windows Biometric Service heap buffer overflow](https://junglewise.ai/threats/cve-2026-83981-microsoft-windows-biometric-service-heap-buffer-overflow)
- [Microsoft Windows Biometric Service heap-based buffer overflow](https://junglewise.ai/threats/cve-2026-83980-microsoft-windows-biometric-service-heap-based-buffer-overflow)