What is CVE-2019-16791?

CVE-2019-16791 is a medium-severity vulnerability in Postfix-Mta-Sts-Resolver Project, classified under CWE-757. CVSS score: 6.9/10. Published 2020-01-22.

How severe is CVE-2019-16791?

Medium severity. CVSS v3 base score is 6.9 out of 10.

Vulnerability in Postfix-Mta-Sts-Resolver Project

CVE-2019-16791

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.

Published 2020-01-22 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 6.9 (Medium). Vector: CVSS:3.1/AV:L/AC:H/PR:H/UI:R/S:C/C:H/I:H/A:N.

EPSS exploit prediction

EPSS: 0.009 (57.7th percentile), scored 2026-10-19.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 58th percentile — 57.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.008 · newest: 0.009 · change: +0.001

Affected products

Postfix-Mta-Sts-Resolver Project
Snawoot Postfix-Mta-Sts-Resolver — versions < 0.5.1

Weakness classification (CWE)

CWE-757

References

github.com/Snawoot/postfix-mta-sts-resolver/security/advisories/GHSA-h92m-42h4-… (Patch, Third Party Advisory)
gist.github.com/Snawoot/b9da85d6b26dea5460673b29df1adc6b (Patch, Third Party Advisory)

Frequently asked questions

What is CVE-2019-16791?: CVE-2019-16791 is a medium-severity vulnerability in Postfix-Mta-Sts-Resolver Project, classified under CWE-757. CVSS score: 6.9/10. Published 2020-01-22.
How severe is CVE-2019-16791?: Medium severity. CVSS v3 base score is 6.9 out of 10.