Windows App Store race condition enables remote privilege escalation on widely deployed Windows systems; impacts broad user base and can lead to full system compromise.
CVE-2026-42900
Race condition in Windows App Store enabling remote privilege escalation.
Is CVE-2026-42900 being exploited?
Not confirmed. CVE-2026-42900 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.54% probability of exploitation in the next 30 days.
How severe is CVE-2026-42900?
CVE-2026-42900 is rated High with a CVSS score of 8.1. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-42900?
Yes. A fix has been recorded for CVE-2026-42900. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-42900 affect?
CVE-2026-42900 affects Microsoft Windows App Store, Windows client OS (Windows 10/11 and later). Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-42900?
Apply vendor patch immediately when released; restrict App Store network access and monitor for privilege escalation.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Remote privilege escalation via race condition in Windows App Store allowing attacker to gain Administrator/SYSTEM privileges over a network.
Immediate action required
- affected>= 10.0.14393.0 and < 10.0.14393.9339
- affected>= 10.0.17763.0 and < 10.0.17763.9020
- affected>= 10.0.19044.0 and < 10.0.19044.7548
- affected>= 10.0.19045.0 and < 10.0.19045.7548
- affected>= 10.0.26100.0 and < 10.0.26100.8875
- affected>= 10.0.26200.0 and < 10.0.26200.8875
- affected>= 10.0.28000.0 and < 10.0.28000.2525
- affected>= 10.0.14393.0 and < 10.0.14393.9339
- affected>= 10.0.14393.0 and < 10.0.14393.9339
- affected>= 10.0.17763.0 and < 10.0.17763.9020
- affected>= 10.0.17763.0 and < 10.0.17763.9020
- affected>= 10.0.20348.0 and < 10.0.20348.5386
- affected>= 10.0.26100.0 and < 10.0.26100.33158
- affected>= 10.0.26100.0 and < 10.0.26100.33158
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.