FKIE_CVE-2026-20856
Vulnerability from fkie_nvd - Published: 2026-01-13 18:16 - Updated: 2026-01-15 15:20
Severity ?
Summary
Improper input validation in Windows Server Update Service allows an unauthorized attacker to execute code over a network.
References
| URL | Tags | ||
|---|---|---|---|
| secure@microsoft.com | https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20856 | Vendor Advisory |
Impacted products
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"value": "Improper input validation in Windows Server Update Service allows an unauthorized attacker to execute code over a network."
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"id": "CVE-2026-20856",
"lastModified": "2026-01-15T15:20:22.237",
"metrics": {
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"baseScore": 8.1,
"baseSeverity": "HIGH",
"confidentialityImpact": "HIGH",
"integrityImpact": "HIGH",
"privilegesRequired": "NONE",
"scope": "UNCHANGED",
"userInteraction": "NONE",
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"published": "2026-01-13T18:16:14.313",
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}
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Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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