CVE-2025-48809

Local information disclosure via processor-optimized security code

Published Jul 8, 2025 · Updated Feb 13, 2026

Information disclosure in Microsoft Windows Kernel before build 10.0.26100.4652 allows local users to read sensitive information. Processor optimization removes or changes security-critical kernel code, but Microsoft has not identified the affected routine or disclosed which data can be read. Local low-privileged access is required, and exploitation needs no user interaction; the documented impact is limited to confidentiality.

CVSS severity5.5
Medium
EPSS probability0.43%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Information disclosure in Microsoft Windows Kernel before build 10.0.26100.4652 allows local users to read sensitive information. Processor optimization removes or changes security-critical kernel code, but Microsoft has not identified the affected routine or disclosed which data can be read. Local low-privileged access is required, and exploitation needs no user interaction; the documented impact is limited to confidentiality.

The record

CVE
CVE-2025-48809
Published
Jul 8, 2025
Updated
Feb 13, 2026
Vendor
Microsoft
Product
Windows Server 2025 (Server Core installation)
Classifications
CWE-1037, CAPEC-663
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Jul 8, 2025CVE publishedPublication date reported by the CVE source.
  2. Feb 13, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=10.0.26100.0 <10.0.26100.4652

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Microsoft · Windows Server 2025 (Server Core installation)version=10.0.26100.0 <10.0.26100.4652
Microsoft · Windows 11, version 24H2version=10.0.26100.0 <10.0.26100.4652
Microsoft · Windows Server 2025version=10.0.26100.0 <10.0.26100.4652

Published CVSS scores

5.5Microsoft CorporationCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-1037Processor Optimization Removal or Modification of Security-critical Code
CAPEC-663Exploitation of Transient Instruction Execution

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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