XXE in Microsoft Internet Explorer

Published: 2019-04-15

Risk	Medium
Patch available	NO
Number of vulnerabilities	1
CVE-ID	N/A
CWE-ID	CWE-611
Exploitation vector	Network
Public exploit	Public exploit code for vulnerability #1 is available.
Vulnerable software Subscribe	Microsoft Internet Explorer Client/Desktop applications / Web browsers
Vendor	Microsoft

Security Bulletin

This security bulletin contains one medium risk vulnerability.

1) Improper restriction of XML external entity reference (XXE)

EUVDB-ID: #VU18256

Risk: Medium

CVSSv3.1: 4.5 [CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:N/A:N/E:P/RL:U/RC:C]

CVE-ID: N/A

CWE-ID: CWE-611 - Improper Restriction of XML External Entity Reference ('XXE')

Exploit availability: No

Description

The vulnerability allows a remote attacker to gain access to sensitive information on the system.

The vulnerability exists due to improper restriction of XML external entity reference when processing .mht files. A remote attacker can trick the victim into opening a specially crafted .mht file and ready contents of arbitrary file on the system with privilege of the current user.

Mitigation

Cybersecurity Help is currently unaware of any official solution to address this vulnerability.

Vulnerable software versions

Microsoft Internet Explorer: 9 - 11

External links

http://hyp3rlinx.altervista.org/advisories/MICROSOFT-INTERNET-EXPLORER-v11-XML-EXTERNAL-ENTITY-INJECTION-0DAY.txt

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

How the attacker can exploit this vulnerability?

The attacker would have to trick the victim to visit a specially crafted website.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability. However, proof of concept for this vulnerability is available.