CVE-2019-9801

MEDIUM

Firefox < 66.0, Firefox ESR < 60.6, Thunderbird < 60.6 - External Protocol Handler Execution

Title source: llm
STIX 2.1

Description

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.

References (4)

Core 4
Core References
Issue Tracking, Permissions Required, Vendor Advisory x_refsource_misc
https://bugzilla.mozilla.org/show_bug.cgi?id=1527717

Scores

CVSS v3 5.3
EPSS 0.0037
EPSS Percentile 58.8%
Attack Vector NETWORK
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

Details

CWE
CWE-20
Status published
Products (3)
mozilla/firefox < 66.0
mozilla/firefox_esr < 60.6
mozilla/thunderbird < 60.6
Published Apr 26, 2019
Tracked Since Feb 18, 2026