XXE in Microsoft Internet Explorer

Published: 2019-04-15

Severity	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	Microsoft Internet Explorer Subscribe
Vendor	Microsoft

Security Advisory

This security advisory describes one medium risk vulnerability.

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

Severity: Medium

CVSSv3: 4.5 [CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:N/A:N/E:P/RL:U/RC:C] [PCI]

CVE-ID: N/A

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

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, 10, 11

CPE

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.