CVE-2018-12370: Canonical Ubuntu Linux

High severity, CVSS 8.8. EPSS: 1.1% chance of exploitation in the next 30 days.

In Reader View SameSite cookie protections are not checked on exiting. This allows for a payload to be triggered when Reader View is exited if loaded by a malicious site while Reader mode is active, bypassing CSRF protections. This vulnerability affects Firefox < 61.

Affected products

• Canonical Ubuntu Linux: version 14.04 only; version 16.04 only; version 17.10 only; version 18.04 only
• Mozilla Firefox: before 61.0 (fixed in 61.0)

Published 2018-10-18. Last modified 2026-06-17.