CVE-2017-7761

The Mozilla Maintenance Service "helper.exe" application creates a temporary directory writable by non-privileged users. When this is combined with creation of a junction (a form of symbolic link), protected files in the target directory of the junction can be deleted by the Mozilla Maintenance Service, which has privileged access. Note: This attack requires local system access and only affects Windows. Other operating systems are not affected. This vulnerability affects Firefox ESR < 52.2 and Firefox < 54.

• CWE-276

• http://www.securityfocus.com/bid/99057Third Party Advisory, VDB Entry
• http://www.securitytracker.com/id/1038689Third Party Advisory, VDB Entry
• https://bugzilla.mozilla.org/show_bug.cgi?id=1215648Issue Tracking, Vendor Advisory
• https://sourceforge.net/p/nsis/bugs/1125/Issue Tracking, Third Party Advisory
• https://www.mozilla.org/security/advisories/mfsa2017-15/Vendor Advisory
• https://www.mozilla.org/security/advisories/mfsa2017-16/Vendor Advisory
• http://www.securityfocus.com/bid/99057Third Party Advisory, VDB Entry
• http://www.securitytracker.com/id/1038689Third Party Advisory, VDB Entry
• https://bugzilla.mozilla.org/show_bug.cgi?id=1215648Issue Tracking, Vendor Advisory
• https://sourceforge.net/p/nsis/bugs/1125/Issue Tracking, Third Party Advisory
• https://www.mozilla.org/security/advisories/mfsa2017-15/Vendor Advisory
• https://www.mozilla.org/security/advisories/mfsa2017-16/Vendor Advisory

Published

Jun 11, 2018

Last Modified

Jun 17, 2026

Status

Modified

• How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
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