CVE-2025-21188

Local privilege escalation via improper link resolution

Published Feb 11, 2025 · Updated Feb 26, 2026

Link-following in Microsoft Azure Network Watcher VM Extension before 1.4.3563.1 allows local users to gain elevated privileges. The extension improperly resolves a link before accessing a file, but Microsoft has not disclosed the affected file operation or path. Exploitation requires local access and high privileges and permits protected data modification and service interruption without confidentiality loss.

CVSS severity6.0
Medium
EPSS probability0.71%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Link-following in Microsoft Azure Network Watcher VM Extension before 1.4.3563.1 allows local users to gain elevated privileges. The extension improperly resolves a link before accessing a file, but Microsoft has not disclosed the affected file operation or path. Exploitation requires local access and high privileges and permits protected data modification and service interruption without confidentiality loss.

The record

CVE
CVE-2025-21188
Published
Feb 11, 2025
Updated
Feb 26, 2026
Vendor
Microsoft
Product
Azure Network Watcher Agent VM Extension
Classifications
CWE-59, T1068
Attack vector
local
Privileges
admin

Timeline

How it unfolded

  1. Feb 11, 2025CVE publishedPublication date reported by the CVE source.
  2. Feb 26, 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=1.0.0.0 <1.4.3563.1

What conditions does exploitation require?

Attack vectorlocal
Required privilegesadmin

What is affected?

Microsoft · Azure Network Watcher Agent VM Extensionversion=1.0.0.0 <1.4.3563.1

Published CVSS scores

6.0Microsoft CorporationCVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:H/A:H

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 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-59Improper Link Resolution Before File Access ('Link Following')
T1068Exploitation for Privilege Escalation

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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