CVE-2017-5422: Mozilla Firefox

High severity, CVSS 7.5. EPSS: 2.4% chance of exploitation in the next 30 days.

If a malicious site uses the "view-source:" protocol in a series within a single hyperlink, it can trigger a non-exploitable browser crash when the hyperlink is selected. This was fixed by no longer making "view-source:" linkable. This vulnerability affects Firefox < 52 and Thunderbird < 52.

Affected products

  • Mozilla Firefox: before 52.0 (fixed in 52.0)
  • Mozilla Thunderbird: before 52.0 (fixed in 52.0)

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