CVE-2021-33764

Exploitation

Not assessed. CISA has not published an exploitation assessment for this record, and it is not in the KEV catalog. That is an absence of assessment, not a finding of no risk.

SSVC decision

Not assessed by CISA

EPSS probability

3.04% probability of exploitation activity in the next 30 days.

EPSS percentile

Equal to or higher than the score of 87.1% of scored records. A rank, not a probability.

NVD base score

5.9 (CVSS v3.x), scored by the NVD independently of the CNA.

NVD CVSS vector

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N

NVD analysis status

Modified. NVD last modified this record on 2026-08-10.

Red Hat severity

No Red Hat rating. Red Hat rates the CVEs that affect its products.

Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.

Published

2021-07-14 17:53Z5 YR AGO

Last updated

2026-08-10 15:11Z2 MO AGO

Reserved

2021-05-28

Assigning CNA

microsoft

Record state

PUBLISHED

Severity

Medium (CVSS 5.9)

CNA CVSS vector

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N/E:U/RL:O/RC:C

Weaknesses

No CWE assigned

Data version

5.2

Document digest

c701fba2046aaf067c1234ca5377d4bef5a543c2ed0b3f6b1df19ffc473bef23

• msrc.microsoft.comWindows Key Distribution Center Information Disclosure Vulnerabilityhttps://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-33764vendor-advisorypatch
• portal.msrc.microsoft.comhttps://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-33764x_refsource_MISC