This update for MozillaFirefox ESR 52.5 fixes the following issues:
Security issues fixed: - CVE-2017-7826: Memory safety bugs fixed (bsc#1068101). - CVE-2017-7828: Use-after-free of PressShell while restyling layout (bsc#1068101). - CVE-2017-7830: Cross-origin URL information leak through Resource Timing API (bsc#1068101).
Mozilla Foundation Security Advisory (MFSA 2017-25): - https://www.mozilla.org/en-US/security/advisories/mfsa2017-25/