CVE-2019-9801

MediumCVSS 5.3/10Last modified Jun 17, 2026

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.

Metrics

CVSS 3.0 5.3/10CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

Weakness enumeration

CWE-20

Affected software

Vendor	Product	Versions
Mozilla	Thunderbird	>= unspecified, < 60.6
Mozilla	Firefox ESR	>= unspecified, < 60.6
Mozilla	Firefox	>= unspecified, < 66

References

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

Timeline

Published: Apr 26, 2019
Last modified: Jun 17, 2026
NVD status: Modified

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