Vulnerability identifier: #VU12544

Vulnerability risk: Low

CVSSv3.1: 6.4 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L/E:U/RL:O/RC:C]

CVE-ID: CVE-2018-5163

CWE-ID: CWE-264

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 bypass security restrictions on the target system.

The weakness exists due to replacing of cached data in JavaScript start-up bytecode cache. A remote attacker with full control over a content process can replace the alternate data resources stored in the JavaScript Start-up Bytecode Cache (JSBC) for other JavaScript code, run the executed script with the parent process' privileges and escaping the sandbox on content processes.

Mitigation
Update to version 60.0.

Vulnerable software versions

Mozilla Firefox: 59.0 - 59.0.2

---

External links
http://www.mozilla.org/en-US/security/advisories/mfsa2018-11/

---

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.