CVE-2017-7783

If a long user name is used in a username/password combination in a site URL (such as " http://UserName:Password@example.com"), the resulting modal prompt will hang in a non-responsive state or crash, causing a denial of service. This vulnerability affects Firefox < 55.

• CWE-20

• http://www.securityfocus.com/bid/100401Third Party Advisory, VDB Entry
• http://www.securitytracker.com/id/1039124Third Party Advisory, VDB Entry
• https://bugzilla.mozilla.org/show_bug.cgi?id=1360842Exploit, Issue Tracking, Patch
• https://www.exploit-db.com/exploits/43020/Third Party Advisory, VDB Entry
• https://www.mozilla.org/security/advisories/mfsa2017-18/Vendor Advisory
• http://www.securityfocus.com/bid/100401Third Party Advisory, VDB Entry
• http://www.securitytracker.com/id/1039124Third Party Advisory, VDB Entry
• https://bugzilla.mozilla.org/show_bug.cgi?id=1360842Exploit, Issue Tracking, Patch
• https://www.exploit-db.com/exploits/43020/Third Party Advisory, VDB Entry
• https://www.mozilla.org/security/advisories/mfsa2017-18/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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