CVE-2018-5121

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.

• CWE-20

• 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

Published

Jun 11, 2018

Last Modified

Jun 17, 2026

Status

Modified

• How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
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