CVE-2020-25739: Canonical Ubuntu Linux

Medium severity, CVSS 6.1. EPSS: 1.4% chance of exploitation in the next 30 days.

An issue was discovered in the gon gem before gon-6.4.0 for Ruby. MultiJson does not honor the escape_mode parameter to escape fields as an XSS protection mechanism. To mitigate, json_dumper.rb in gon now does escaping for XSS by default without relying on MultiJson.

Affected products

• Canonical Ubuntu Linux: version 18.04 only
• Debian Debian Linux: version 9.0 only
• Gon Project Gon: before 6.4.0 (fixed in 6.4.0)

Published 2020-09-23. Last modified 2026-06-17.