CVE-2017-7823: Debian Linux

Medium severity, CVSS 5.4. EPSS: 1.5% chance of exploitation in the next 30 days.

The content security policy (CSP) "sandbox" directive did not create a unique origin for the document, causing it to behave as if the "allow-same-origin" keyword were always specified. This could allow a Cross-Site Scripting (XSS) attack to be launched from unsafe content. This vulnerability affects Firefox < 56, Firefox ESR < 52.4, and Thunderbird < 52.4.

Affected products

• Debian Debian Linux: version 7.0 only; version 8.0 only; version 9.0 only
• Mozilla Firefox: before 52.4.0 (fixed in 52.4.0); before 56.0 (fixed in 56.0)
• Mozilla Thunderbird: before 52.4.0 (fixed in 52.4.0)
• 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.