CVE-2018-5121

Name: CVE-2018-5121
Creator: NVD / NIST
Published: 2018-06-11T21:29:13.717+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

UnknownEPSS 1.47%

Last modified Jun 17, 2026

CVE-2018-5121 is a vulnerability of currently unknown severity. Low descenders on some Tibetan characters in several fonts on OS X are clipped when rendered in the addressbar. When used as part of an Internationalized Domain Name (IDN) this can be used for domain name spoofing attacks. EPSS estimates a 1.47% chance of exploitation in the next 30 days.

Description

Low descenders on some Tibetan characters in several fonts on OS X are clipped when rendered in the addressbar. When used as part of an Internationalized Domain Name (IDN) this can be used for domain name spoofing attacks. Note: This attack only affects OS X operating systems. Other operating systems are unaffected. This vulnerability affects Firefox < 58.

Metrics

EPSS Probability

1.47%

70.5th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-20

Affected Software

Vendor	Product	Versions
Mozilla	Firefox	<= 57.0.4

References

http://www.securityfocus.com/bid/102786Third Party Advisory, VDB Entry
http://www.securitytracker.com/id/1040270Third Party Advisory, VDB Entry
https://bugzilla.mozilla.org/show_bug.cgi?id=1402368Issue Tracking, Permissions Required
https://www.mozilla.org/security/advisories/mfsa2018-02/Vendor Advisory
http://www.securityfocus.com/bid/102786Third Party Advisory, VDB Entry
http://www.securitytracker.com/id/1040270Third Party Advisory, VDB Entry
https://bugzilla.mozilla.org/show_bug.cgi?id=1402368Issue Tracking, Permissions Required
https://www.mozilla.org/security/advisories/mfsa2018-02/Vendor Advisory

Timeline

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

Frequently Asked Questions

What is CVE-2018-5121?

How severe is CVE-2018-5121?

Severity scoring for CVE-2018-5121 is pending analysis. The EPSS model estimates a 1.47% probability of exploitation in the next 30 days.

How do I fix CVE-2018-5121?

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-2018-5121?

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

Scan your code now

Source: NVD / NIST