CVE-2022-22739

Name: CVE-2022-22739
Creator: NVD / NIST
Published: 2022-12-22T20:15:14.353+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 6.5/10EPSS 0.68%

Last modified Jun 17, 2026

CVE-2022-22739 is a medium-severity vulnerability rated 6.5/10 on the CVSS scale. Malicious websites could have tricked users into accepting launching a program to handle an external URL protocol. This vulnerability affects Firefox ESR < 91.5, Firefox < 96, and Thunderbird < 91.5.. EPSS estimates a 0.68% chance of exploitation in the next 30 days.

Description

Malicious websites could have tricked users into accepting launching a program to handle an external URL protocol. This vulnerability affects Firefox ESR < 91.5, Firefox < 96, and Thunderbird < 91.5.

Metrics

CVSS 3.1

6.5/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N

EPSS Probability

0.68%

47.7th percentile

Probability of exploitation in the next 30 days. Learn more

Affected Software

Vendor	Product	Versions
Mozilla	Firefox	< 96.0
Mozilla	Firefox Esr	< 91.5
Mozilla	Thunderbird	< 91.5

References

https://bugzilla.mozilla.org/show_bug.cgi?id=1744158Exploit, Issue Tracking, Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2022-01/Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2022-02/Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2022-03/Vendor Advisory
https://bugzilla.mozilla.org/show_bug.cgi?id=1744158Exploit, Issue Tracking, Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2022-01/Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2022-02/Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2022-03/Vendor Advisory

Timeline

Published: Dec 22, 2022
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2022-22739?

Malicious websites could have tricked users into accepting launching a program to handle an external URL protocol. This vulnerability affects Firefox ESR < 91.5, Firefox < 96, and Thunderbird < 91.5.

How severe is CVE-2022-22739?

CVE-2022-22739 has a CVSS score of 6.5/10 (MEDIUM severity). The EPSS model estimates a 0.68% probability of exploitation in the next 30 days.

How do I fix CVE-2022-22739?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2022-22739?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST