CVE-2019-9801

Firefox will accept any registered Program ID as an external protocol handler and offer to launch this local application when given a matching URL on Windows operating systems. This should only happen if the program has specifically registered itself as a "URL Handler" in the Windows registry. *Note: This issue only affects Windows operating systems. Other operating systems are unaffected.*. This vulnerability affects Thunderbird < 60.6, Firefox ESR < 60.6, and Firefox < 66.

• CWE-20

• https://bugzilla.mozilla.org/show_bug.cgi?id=1527717Issue Tracking, Permissions Required, Vendor Advisory
• https://www.mozilla.org/security/advisories/mfsa2019-07/Vendor Advisory
• https://www.mozilla.org/security/advisories/mfsa2019-08/Vendor Advisory
• https://www.mozilla.org/security/advisories/mfsa2019-11/Vendor Advisory
• https://bugzilla.mozilla.org/show_bug.cgi?id=1527717Issue Tracking, Permissions Required, Vendor Advisory
• https://www.mozilla.org/security/advisories/mfsa2019-07/Vendor Advisory
• https://www.mozilla.org/security/advisories/mfsa2019-08/Vendor Advisory
• https://www.mozilla.org/security/advisories/mfsa2019-11/Vendor Advisory

Published

Apr 26, 2019

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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