Privilege escalation via authentication certificate export
Published Oct 14, 2025 · Updated Feb 26, 2026
Weak authentication in Microsoft Exchange Server before the October 2025 updates allows remote authenticated users to elevate privileges. An Exchange cmdlet permits an authenticated user to export the server authentication certificate, authentication material Microsoft disabled from export in the correcting update. Low-privileged network access is required; possession of the exported credential enables privileged impersonation with confidentiality, integrity, and availability consequences.
Summary
What happened
Weak authentication in Microsoft Exchange Server before the October 2025 updates allows remote authenticated users to elevate privileges. An Exchange cmdlet permits an authenticated user to export the server authentication certificate, authentication material Microsoft disabled from export in the correcting update. Low-privileged network access is required; possession of the exported credential enables privileged impersonation with confidentiality, integrity, and availability consequences.
The record
- CVE
- CVE-2025-59249
- Published
- Oct 14, 2025
- Updated
- Feb 26, 2026
- Vendor
- Microsoft
- Product
- Microsoft Exchange Server 2019 Cumulative Update 14
- Classifications
- CWE-1390, T1649
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Oct 14, 2025CVE publishedPublication date reported by the CVE source.
- 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.
- Affected versionversion=15.02.0.0 <15.02.1544.036
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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