CVE-2017-7828: Debian Linux

Critical severity, CVSS 9.8. EPSS: 7.3% chance of exploitation in the next 30 days.

A use-after-free vulnerability can occur when flushing and resizing layout because the "PressShell" object has been freed while still in use. This results in a potentially exploitable crash during these operations. This vulnerability affects Firefox < 57, Firefox ESR < 52.5, and Thunderbird < 52.5.

Affected products

• Debian Debian Linux: version 7.0 only; version 8.0 only; version 9.0 only
• Mozilla Firefox: before 57.0 (fixed in 57.0); before 52.5.0 (fixed in 52.5.0)
• Mozilla Thunderbird: before 52.5.0 (fixed in 52.5.0)
• Red Hat Enterprise Linux Desktop: version 6.0 only; version 7.0 only
• Red Hat Enterprise Linux Server: version 6.0 only; version 7.0 only
• Red Hat Enterprise Linux Server Aus: version 7.4 only
• Red Hat Enterprise Linux Server Eus: version 7.4 only; version 7.5 only
• Red Hat Enterprise Linux Workstation: version 6.0 only; version 7.0 only

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