CVE-2018-8581

KEVRansomware UseMicrosoft Exchange Server Privilege Escalation Vulnerability

Description

A privilege escalation vulnerability exists in Microsoft Exchange Server. An attacker who successfully exploited this vulnerability could attempt to impersonate any other user of the Exchange server.

An elevation of privilege vulnerability exists in Microsoft Exchange Server, aka "Microsoft Exchange Server Elevation of Privilege Vulnerability." This affects Microsoft Exchange Server.

CVSS 3.1 vectorCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N

PublishedNov 14, 2018

Last modifiedJun 17, 2026

Added to KEVMar 3, 2022

Remediation dueMar 17, 2022

References

securityfocus.com/bid/105837Broken LinkThird Party Advisory
securitytracker.com/id/1042141Broken LinkThird Party Advisory
portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2018-8581PatchVendor Advisory
cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2018-8581US Government Resource

0 recent articles mention this CVE

Risk assessment · Critical

Actively exploited and used by ransomware crews. Patch immediately.

Exploitation: Confirmed in the wild (CISA KEV)
Federal remediation deadline: Overdue by 1685 days
Ransomware: Used in known ransomware campaigns
CVSS: 7.4 HIGH
EPSS (30-day exploit probability): 27.4% · top 2% of all CVEs
Weakness: NVD-CWE-noinfo
Attack vector: Network, remotely reachable
Preconditions: No privileges and no user interaction

Recommended actions

1.Apply updates per vendor instructions.
2.Treat as emergency change: patch or isolate internet-facing instances first.
3.Review exposure: confirm which instances are reachable from the internet and restrict access until patched.
4.Hunt for compromise: review logs for the disclosure window, not just from the patch date.
5.Verify offline/immutable backups and segment the affected systems. This flaw is used for ransomware initial access.

Assessment is derived automatically from the live signals above; verify against your own asset inventory.