An elevation of privilege vulnerability exists when Microsoft Exchange Outlook Web Access (OWA) fails to properly handle web requests, aka…

published 2018-05-09 8y ago modified 2026-06-17 4mo ago also EUVD-2018-19830

cvss: 5.4; version 3.0, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 3.5%; EPSS 3.5% chance of exploitation in 30 days, percentile 89%
public exploits: 0; none known

An elevation of privilege vulnerability exists when Microsoft Exchange Outlook Web Access (OWA) fails to properly handle web requests, aka "Microsoft Exchange Elevation of Privilege Vulnerability." This affects Microsoft Exchange Server.

Patch / fix

links 1

portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2018-8159 advisory

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Exploit prediction

3.51% chance of exploitation in the next 30 days, higher than 89% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by	version	score	vector
NVD	3.0	5.4	CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N
NVD	2.0	5.8	AV:N/AC:M/Au:N/C:P/I:P/A:N

Affected products

Microsoft Microsoft Exchange Server

Classification

Weakness

CWE-79 Improper Neutralization of Input During Web Page Generation

Technology feeds

Microsoft Exchange rss critical rss

References

portal.msrc.microsoft.com /en-US/security-guidance/advisory/CVE-2018-8159
patch, vendor-advisory
securityfocus.com /bid/104056
vdb-entry, third-party-advisory
securitytracker.com /id/1040850
vdb-entry, third-party-advisory

Sources

CVE List CVE-2018-8159
NVD CVE-2018-8159

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