CVE-2017-7843: Debian Linux

High severity, CVSS 7.5. EPSS: 3% chance of exploitation in the next 30 days.

When Private Browsing mode is used, it is possible for a web worker to write persistent data to IndexedDB and fingerprint a user uniquely. IndexedDB should not be available in Private Browsing mode and this stored data will persist across multiple private browsing mode sessions because it is not cleared when exiting. This vulnerability affects Firefox ESR < 52.5.2 and Firefox < 57.0.1.

Affected products

• Debian Debian Linux: version 7.0 only; version 8.0 only; version 9.0 only
• Mozilla Firefox: before 57.0.1 (fixed in 57.0.1); before 52.5.2 (fixed in 52.5.2)
• 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.