CVE-2023-21550: Windows Cryptographic Information Disclosure Vulnerability

Severity: medium (CVSS 5.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.6% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2023-01-10 · updated 2026-06-17
Weakness: CWE-20

Description

Windows Cryptographic Information Disclosure Vulnerability

Affected products

Microsoft Windows 10: all versions
Microsoft Windows 10 20H2: all versions
Microsoft Windows 10: all versions
Microsoft Windows 10: all versions
Microsoft Windows 11 21H2: all versions
Microsoft Windows 11: all versions
Microsoft Windows Server 2019: all versions
Microsoft Windows Server 2022: all versions
Microsoft Windows 10: from 10.0.17763.0 before 10.0.17763.3887 — fixed in 10.0.17763.3887
Microsoft Windows 10 20H2: from 10.0.0 before 10.0.19042.2486 — fixed in 10.0.19042.2486
Microsoft Windows 10: from 10.0.19043.0 before 10.0.19044.2486 — fixed in 10.0.19044.2486
Microsoft Windows 10: from 10.0.19045.0 before 10.0.19045.2486 — fixed in 10.0.19045.2486
Microsoft Windows 11 21H2: from 10.0.0 before 10.0.22000.1455 — fixed in 10.0.22000.1455
Microsoft Windows 11: from 10.0.22621.0 before 10.0.22621.1105 — fixed in 10.0.22621.1105
Microsoft Windows Server 2019: from 10.0.17763.0 before 10.0.17763.3887 — fixed in 10.0.17763.3887
Microsoft Windows Server 2022: from 10.0.20348.0 before 10.0.20348.1487 — fixed in 10.0.20348.1487

How to fix

Upgrade to a fixed version: Microsoft Windows 10 10.0.17763.3887; Microsoft Windows 10 20H2 10.0.19042.2486; Microsoft Windows 10 10.0.19044.2486; Microsoft Windows 10 10.0.19045.2486; Microsoft Windows 11 21H2 10.0.22000.1455; Microsoft Windows 11 10.0.22621.1105; Microsoft Windows Server 2019 10.0.17763.3887; Microsoft Windows Server 2022 10.0.20348.1487. Check the vendor advisory for mitigations.

References

Get alerted when CVE-2023-21550 or the next vulnerability affects your stack