CVE-2026-83766

Exploitation

Assessed, none found. CISA's assessment recorded neither public exploit code nor evidence of exploitation when it was made.

SSVC decision

• ExploitationnoneCISA recorded no public exploit code and no evidence of exploitation.
• AutomatablenoAt least one step from reconnaissance to exploitation cannot be reliably automated.
• Technical ImpactpartialSuccessful exploitation gives limited control of the vulnerable component.

CISA publishes the decision points, not a final SSVC decision. The decision also depends on mission and well-being impact, which is a property of your deployment rather than of the vulnerability.

EPSS probability

0.40% probability of exploitation activity in the next 30 days.

EPSS percentile

Equal to or higher than the score of 34.7% of scored records. A rank, not a probability.

NVD base score

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

NVD CVSS vector

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

NVD analysis status

Awaiting Analysis. NVD last modified this record on 2026-10-16.

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

2026-10-13 19:00Z15 DAYS AGO

Last updated

2026-10-28 18:17Z16 HR AGO

Reserved

2026-08-31

Assigning CNA

microsoft

Record state

PUBLISHED

Severity

Medium (CVSS 4.2)

CNA CVSS vector

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

Weaknesses

• CWE-863Incorrect AuthorizationClass

Data version

5.2

Document digest

8927167b507e2772190f98aac0f75976ed2ac4642e5937ca5b5cef036599503f

• msrc.microsoft.comWindows Hyper-V Security Feature Bypass Vulnerabilityhttps://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-83766vendor-advisorypatch