CVE-2018-5121: Input Validation

Published Jan 23, 2018
·
Updated

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.

Affected Software

3 affected componentsFixes available
Mozilla Firefox<58
58
Mozilla Firefox<=57.0.4
Apple iOS and macOS

Event History

Jan 23, 2018
CVE Published
12:00 AM
Jun 11, 2018
CVE Published
via MITRE·09:00 PM
Data Sourced
via MITRE·09:00 PM
DescriptionWeakness

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is CVE-2018-5121?

CVE-2018-5121 is a vulnerability that affects certain fonts in Mozilla Firefox on OS X, allowing for domain name spoofing attacks.

2

How does CVE-2018-5121 affect OS X?

CVE-2018-5121 affects OS X by causing low descenders on some Tibetan characters in certain fonts to be clipped when rendered in the address bar.

3

Does CVE-2018-5121 affect other operating systems?

No, CVE-2018-5121 only affects OS X operating systems.

4

What is the severity of CVE-2018-5121?

CVE-2018-5121 has a severity score of 5.3 (medium).

5

How can CVE-2018-5121 be fixed?

To fix CVE-2018-5121, update Mozilla Firefox to version 58 or later.

Contact

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