CVE-2017-7763: Debian Linux

Medium severity, CVSS 5.3. EPSS: 1.1% chance of exploitation in the next 30 days.

Default fonts on OS X display some Tibetan characters as whitespace. When used in the addressbar as part of an 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 < 54, Firefox ESR < 52.2, and Thunderbird < 52.2.

Affected products

• Debian Debian Linux: version 8.0 only; version 9.0 only
• Mozilla Firefox: before 52.2.0 (fixed in 52.2.0); before 54.0 (fixed in 54.0)
• Mozilla Thunderbird: before 52.2.0 (fixed in 52.2.0)

Published 2018-06-11. Last modified 2026-06-17.