CVE-2018-12399

Name: CVE-2018-12399
Creator: NVD / NIST
Published: 2019-02-28T18:29:01.023+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

UnknownEPSS 1.36%

Last modified Jun 17, 2026

CVE-2018-12399 is a vulnerability of currently unknown severity. When a new protocol handler is registered, the API accepts a title argument which can be used to mislead users about which domain is registering the new protocol. This may result in the user approving a protocol handler that they otherwise would not have. EPSS estimates a 1.36% chance of exploitation in the next 30 days.

Description

When a new protocol handler is registered, the API accepts a title argument which can be used to mislead users about which domain is registering the new protocol. This may result in the user approving a protocol handler that they otherwise would not have. This vulnerability affects Firefox < 63.

Metrics

EPSS Probability

1.36%

68.1th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-287

Affected Software

Vendor	Product	Versions
Mozilla	Firefox	< 63.0
Canonical	Ubuntu Linux	14.04
Canonical	Ubuntu Linux	16.04
Canonical	Ubuntu Linux	18.04
Canonical	Ubuntu Linux	18.10

References

http://www.securityfocus.com/bid/105721Third Party Advisory, VDB Entry
http://www.securitytracker.com/id/1041944Third Party Advisory, VDB Entry
https://bugzilla.mozilla.org/show_bug.cgi?id=1490276Issue Tracking, Permissions Required, Vendor Advisory
https://usn.ubuntu.com/3801-1/Third Party Advisory
https://www.mozilla.org/security/advisories/mfsa2018-26/Vendor Advisory
http://www.securityfocus.com/bid/105721Third Party Advisory, VDB Entry
http://www.securitytracker.com/id/1041944Third Party Advisory, VDB Entry
https://bugzilla.mozilla.org/show_bug.cgi?id=1490276Issue Tracking, Permissions Required, Vendor Advisory
https://usn.ubuntu.com/3801-1/Third Party Advisory
https://www.mozilla.org/security/advisories/mfsa2018-26/Vendor Advisory

Timeline

Published: Feb 28, 2019
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2018-12399?

How severe is CVE-2018-12399?

Severity scoring for CVE-2018-12399 is pending analysis. The EPSS model estimates a 1.36% probability of exploitation in the next 30 days.

How do I fix CVE-2018-12399?

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-2018-12399?

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

Scan your code now

Source: NVD / NIST