CVE-2017-7831: Mozilla Firefox

Medium severity, CVSS 5.3. EPSS: 1.6% chance of exploitation in the next 30 days.

A vulnerability where the security wrapper does not deny access to some exposed properties using the deprecated "_exposedProps_" mechanism on proxy objects. These properties should be explicitly unavailable to proxy objects. This vulnerability affects Firefox < 57.

Affected products

• Mozilla Firefox: up to and including 56.0.2

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