CVE-2019-16791: Postfix-MTA-Sts-Resolver Project Postfix-MTA-Sts-Resolver

Medium severity, CVSS 5.9. EPSS: 0.9% chance of exploitation in the next 30 days.

In postfix-mta-sts-resolver before 0.5.1, All users can receive incorrect response from daemon under rare conditions, rendering downgrade of effective STS policy.

Affected products

• Postfix-MTA-Sts-Resolver Project Postfix-MTA-Sts-Resolver: before 0.5.1 (fixed in 0.5.1)

Published 2020-01-22. Last modified 2026-06-17.