# CVE-2026-42977: Microsoft Windows Push Notifications race condition privilege escalation

Source: https://junglewise.ai/threats/cve-2026-42977-microsoft-windows-push-notifications-race-condition-privilege  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-06-09. Updated: 2026-06-09  
License: CC BY 4.0 with a link back

CVE-2026-42977 · Severity: high · CVSS 7.8 · Published 2026-06-09

A security vulnerability exists in the Windows Push Notification service, which handles the delivery of real-time alerts and updates to applications. An attacker who already has limited access to a computer could exploit this flaw to gain full administrative control over the system. This could allow them to view sensitive data, install malicious software, or disrupt business operations.

Technologies: [Microsoft Windows Push Notifications](https://junglewise.ai/threats/technologies/windows-push-notifications). Vendors: [Microsoft](https://junglewise.ai/threats/vendors/microsoft).

## Quick answers

**Is CVE-2026-42977 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-42977 being exploited in the wild.

**How severe is CVE-2026-42977?** High severity, with a CVSS score of 7.8, published 9 June 2026.

**Which products and versions are affected?** Microsoft Windows Push Notifications.

**Is there a fix for CVE-2026-42977?** 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-2026-42977 attacked?** It is attacked with local access, in an operating system.

**Am I affected by CVE-2026-42977?** Check whether you run Microsoft Windows Push Notifications. 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 race condition (CWE-362) exists in the Windows Push Notifications service due to improper synchronization when accessing shared resources. To exploit this, an attacker must first have local access to the system with low-level privileges. By successfully winning the race condition during concurrent execution, the attacker can achieve a privilege escalation, potentially gaining SYSTEM-level access. The vulnerability is characterized by high complexity (AC:H) and requires local authentication (PR:L), but it allows for a full compromise of confidentiality, integrity, and availability.

## Affected products

- Microsoft Windows Push Notifications

## Timeline

- 2026-06-09: disclosed
- 2026-06-09: advisory

## References

- [https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-42977](https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-42977)

## Related threats

- [Microsoft Windows Push Notifications use after free privilege escalation](https://junglewise.ai/threats/cve-2026-70198-use-after-free-in-windows-push-notifications-allows-an-authorized)
- [Microsoft Windows Push Notifications privilege escalation](https://junglewise.ai/threats/cve-2026-69300-microsoft-windows-push-notifications-privilege-escalation)
- [Microsoft Windows Push Notifications privilege escalation via race condition](https://junglewise.ai/threats/cve-2026-42991-microsoft-windows-push-notifications-privilege-escalation-via)
- [Microsoft Windows Push Notifications race condition privilege escalation](https://junglewise.ai/threats/cve-2026-42979-microsoft-windows-push-notifications-race-condition-privilege)
- [Microsoft Windows Push Notifications information disclosure](https://junglewise.ai/threats/cve-2026-42971-microsoft-windows-push-notifications-information-disclosure)