Remote code execution in Mozilla Firefox

1) Improper input validation

EUVDB-ID: #VU10327

Risk: High

CVSSv3.1: 7.8 [CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2018-5124

CWE-ID: CWE-20 - Improper input validation

Exploit availability: No

Description

The vulnerability allows a remote attacker to compromise vulnerable system.

The vulnerability exists due to absent sanitization of the output in the browser UI when processing HTML fragments created for chrome-privileged documents. A remote attacker can create a specially crafted web page, trick the victim into opening it and execute arbitrary code on the target system.

Mitigation

Update to version 58.0.1.

Vulnerable software versions

Mozilla Firefox: 57.0 - 58.0

External links

http://www.mozilla.org/en-US/security/advisories/mfsa2018-05/
http://bugzilla.mozilla.org/show_bug.cgi?id=1432966

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated user 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.