CVE-2018-8244 — Microsoft Outlook Elevation of Privilege Vulnerability

Executive Summary

An elevation of privilege vulnerability exists when Microsoft Outlook does not validate attachment headers properly. An attacker who successfully exploited the vulnerability could send an email with hidden attachments that would be opened or executed once a victim clicks a link within the email. Note that this does not bypass attachment filters, so blocked attachments will still be excluded. To exploit the vulnerability, the attacker could send a specially crafted email to a victim. The victim would then be required to click on a link within the email to open or execute a malicious attachment. This update addresses the vulnerability by changing the way that Outlook parses attachment headers.

Overview

Important

MS Severity

Not Exploited

MS Exploit Status

Less Likely

MS Exploit Likelihood

Category Elevation of Privilege

Released Jun 12 2018

Last Updated Jun 12 2018

Publicly Disclosed No

CISA KEV Not Listed

Known Exploits None Known

EPSS Score

No EPSS score available for this CVE.

View on FIRST.org

Affected Products

9 affected products

Product	KB Article	Severity	Impact	Restart Required
Microsoft Office 2016 Click-to-Run (C2R) for 32-bit editions	`Click to Run (Security Update)`	Important	Elevation of Privilege	No
Microsoft Office 2016 Click-to-Run (C2R) for 64-bit editions	`Click to Run (Security Update)`	Important	Elevation of Privilege	No
Microsoft Outlook 2010 Service Pack 2 (32-bit editions)	`4022205 (Security Update)`	Important	Elevation of Privilege	Maybe
Microsoft Outlook 2010 Service Pack 2 (64-bit editions)	`4022205 (Security Update)`	Important	Elevation of Privilege	Maybe
Microsoft Outlook 2013 RT Service Pack 1	`4022169 (Security Update)`	Important	Elevation of Privilege	Maybe
Microsoft Outlook 2013 Service Pack 1 (32-bit editions)	`4022169 (Security Update)`	Important	Elevation of Privilege	Maybe
Microsoft Outlook 2013 Service Pack 1 (64-bit editions)	`4022169 (Security Update)`	Important	Elevation of Privilege	Maybe
Microsoft Outlook 2016 (32-bit edition)	`4022160 (Security Update)`	Important	Elevation of Privilege	Maybe
Microsoft Outlook 2016 (64-bit edition)	`4022160 (Security Update)`	Important	Elevation of Privilege	Maybe

Patches

4 patches

Article	Type	Restart
`Click to Run`	Security Update	No
`4022205`	Security Update	Maybe
`4022169`	Security Update	Maybe
`4022160`	Security Update	Maybe

Known Exploits

No known exploits have been linked for this CVE yet. When available, exploit references will be sourced from public repositories and may be unverified, incomplete, or non-functional. Always review code carefully before use in any environment.

Acknowledgments

Jonathan Birch of Microsoft Corporation

References

MSRC Advisory MITRE NVD