CVE-2026-20856HIGH 8.1EPSS p60.6%

CVE-2026-20856CVE-2026-20856

Description

Improper input validation in Windows Server Update Service allows an unauthorized attacker to execute code over a network.

Scoring

CVSS 3.18.1 (HIGH)
VectorCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS1.07% probability of exploitation · percentile 60.6% · 2026-06-18T12:00:27Z
Published2026-01-13
Last modified2026-01-15

Underlying weaknesses· 1

CWE-20

References

  1. https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20856

1

TypeTargetConfidenceTier
WeaknessImproper Input Validationcwe-200%live

Related by meaning· 6

Nearest entities by semantic similarity across the cs-graph corpus.

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Sourced from NVD + FIRST.org EPSS. Curated for EU compliance use cases by Adam Lundqvist, Founder at SQUR.