Vulnerability identifier: #VU15495

Vulnerability risk: Low

CVSSv3.1: 7.7 [CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2018-12396

CWE-ID: CWE-20

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Mozilla Firefox
Client/Desktop applications / Web browsers

Vendor: Mozilla

Description
The vulnerability allows a remote attacker to gain elevated privileges on the target system.

The weakness exists due to a WebExtension can run content scripts in disallowed contexts following navigation or other events. A remote attacker can trick the victim into visiting a specially crafted website containing WebExtension where content scripts should not be run and gain elevated privileges.

Mitigation
Update to version 63.0.

Vulnerable software versions

Mozilla Firefox: 62.0 - 62.0.3

---

External links
http://www.mozilla.org/en-US/security/advisories/mfsa2018-26/

---

Q & A

Can this vulnerability be exploited remotely?

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

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.