SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAnalyzed

CVE-2026-20853

Concurrent execution using shared resource with improper synchronization ('race condition') in Windows WalletService allows an unauthorized attacker to elevate privileges locally.

HIGH 7.4EPSS 0.32%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.32%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

Concurrent execution using shared resource with improper synchronization ('race condition') in Windows WalletService allows an unauthorized attacker to elevate privileges locally.

CVSS 3.1
7.4 HIGHCVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS
0.32% probability · 25th percentile
CISA KEV
Not listed
Weakness
CWE-362
Affected
microsoft/windows 10 1607 · microsoft/windows 10 1809 · microsoft/windows 10 21h2 · microsoft/windows 10 22h2 · microsoft/windows 11 23h2 · microsoft/windows 11 24h2 · microsoft/windows 11 25h2
Source
secure@microsoft.com

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.