Medium (5.3) in kde kmail. EPSS 0.5% chance of exploitation in the next 30 days.
In KDE KMail 19.12.3 (aka 5.13.3), the SMTP STARTTLS option is not honored (and cleartext messages are sent) unless "Server requires authentication" is checked.
Severity
CVSS 3.1
5.3 medium
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N
EPSS
0.5% chance of exploitation in the next 30 days; higher than 44% of CVEs (scores of 2026-10-31)