CVE-2018-5163

Name: CVE-2018-5163
Creator: NVD / NIST
Published: 2018-06-11T21:29:15.517+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

UnknownEPSS 2.11%

Last modified Jun 17, 2026

CVE-2018-5163 is a vulnerability of currently unknown severity. If a malicious attacker has used another vulnerability to gain full control over a content process, they may be able to replace the alternate data resources stored in the JavaScript Start-up Bytecode Cache (JSBC) for other JavaScript code. If the parent process then runs this replaced code, the executed script would be run with the parent process' privileges, escaping the sandbox on content processes. EPSS estimates a 2.11% chance of exploitation in the next 30 days.

Description

If a malicious attacker has used another vulnerability to gain full control over a content process, they may be able to replace the alternate data resources stored in the JavaScript Start-up Bytecode Cache (JSBC) for other JavaScript code. If the parent process then runs this replaced code, the executed script would be run with the parent process' privileges, escaping the sandbox on content processes. This vulnerability affects Firefox < 60.

Metrics

EPSS Probability

2.11%

79.5th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-281

Affected Software

Vendor	Product	Versions
Canonical	Ubuntu Linux	14.04
Canonical	Ubuntu Linux	16.04
Canonical	Ubuntu Linux	17.10
Canonical	Ubuntu Linux	18.04
Mozilla	Firefox	< 60.0

References

http://www.securityfocus.com/bid/104139Third Party Advisory, VDB Entry
http://www.securitytracker.com/id/1040896Third Party Advisory, VDB Entry
https://bugzilla.mozilla.org/show_bug.cgi?id=1426353Issue Tracking, Permissions Required, Vendor Advisory
https://usn.ubuntu.com/3645-1/Third Party Advisory
https://www.mozilla.org/security/advisories/mfsa2018-11/Vendor Advisory
http://www.securityfocus.com/bid/104139Third Party Advisory, VDB Entry
http://www.securitytracker.com/id/1040896Third Party Advisory, VDB Entry
https://bugzilla.mozilla.org/show_bug.cgi?id=1426353Issue Tracking, Permissions Required, Vendor Advisory
https://usn.ubuntu.com/3645-1/Third Party Advisory
https://www.mozilla.org/security/advisories/mfsa2018-11/Vendor Advisory

Timeline

Published: Jun 11, 2018
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2018-5163?

How severe is CVE-2018-5163?

Severity scoring for CVE-2018-5163 is pending analysis. The EPSS model estimates a 2.11% probability of exploitation in the next 30 days.

How do I fix CVE-2018-5163?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2018-5163?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST