CVE-2026-83906

MEDIUM

Published Oct 13, 2026 Modified Oct 13, 2026 CWE-303

Description

Incorrect implementation of authentication algorithm in Windows Shell allows an unauthorized attacker to perform spoofing over a network.

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CVSS v3.1 Score

6.5

MEDIUM

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

EPSS — Exploit Prediction

0.0089

Probability of exploitation

0.59%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-303 CWE-303

References

Other References

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-83906

Frequently Asked Questions

What is CVE-2026-83906? +

Incorrect implementation of authentication algorithm in Windows Shell allows an unauthorized attacker to perform spoofing over a network. It has a CVSS v3.1 base score of 6.5 (MEDIUM).

How severe is CVE-2026-83906? +

CVE-2026-83906 has a CVSS v3.1 score of 6.5 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance. The EPSS score is 0.0089, placing it in the 1th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-83906? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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