CVE-2025-21396Network attack vector

Unauthenticated remote privilege escalation

Published Jan 29, 2025 · Updated Jun 9, 2026

Missing authorization in Microsoft Account allows remote attackers to elevate privileges over the network without authentication. Microsoft has not disclosed the affected request, resource, authorization check, or server-side operation that processes untrusted input. No account or user interaction is required; published Microsoft impacts are limited to low-integrity changes and service interruption.

CVSS severity8.2
High
EPSS probability0.70%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Missing authorization in Microsoft Account allows remote attackers to elevate privileges over the network without authentication. Microsoft has not disclosed the affected request, resource, authorization check, or server-side operation that processes untrusted input. No account or user interaction is required; published Microsoft impacts are limited to low-integrity changes and service interruption.

The record

CVE
CVE-2025-21396
Published
Jan 29, 2025
Updated
Jun 9, 2026
Vendor
Microsoft
Product
Microsoft account
Classifications
CWE-862, T1068
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jan 29, 2025CVE publishedPublication date reported by the CVE source.
  2. Jun 9, 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=-

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Microsoft · Microsoft accountversion=-

Published CVSS scores

8.2Microsoft CorporationCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H
9.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/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.

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No observations available

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

Weakness, pattern, technique

CWE-862Missing Authorization
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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