Vulnerability in Mozilla Thunderbird

CVE-2020-12398

If Thunderbird is configured to use STARTTLS for an IMAP server, and the server sends a PREAUTH response, then Thunderbird will continue with an unencrypted connection, causing email data to be sent without protection. This vulnerability affects Thunderbird < 68.9.0.

EPSS: 0.010 (58.5th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2020-12398?
CVE-2020-12398 is a high-severity vulnerability in Mozilla Thunderbird, classified under Cleartext Transmission of Sensitive Information. CVSS score: 7.5/10. Published 2020-07-09.
How severe is CVE-2020-12398?
High severity. CVSS v3 base score is 7.5 out of 10.