CVE-2018-5132: Canonical Ubuntu Linux

Medium severity, CVSS 6.5. EPSS: 1.5% chance of exploitation in the next 30 days.

The Find API for WebExtensions can search some privileged pages, such as "about:debugging", if these pages are open in a tab. This could allow a malicious WebExtension to search for otherwise protected data if a user has it open. This vulnerability affects Firefox < 59.

Affected products

• Canonical Ubuntu Linux: version 14.04 only; version 16.04 only; version 17.10 only
• Mozilla Firefox: before 59.0 (fixed in 59.0)

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