CVE-2019-16791 json
downgrade of effective Strict Transport Security (STS) policy in postfix-mta-sts-resolver
published 2019-07-05 7 y ago modified 2026-09-10 1 mo ago also GHSA-h92m-42h4-82f6 , PYSEC-2020-174 , EUVD-2020-0149
- cvss
- 6.9
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.9%
- EPSS 0.9% chance of exploitation in 30 days, percentile 58%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- pypi postfix-mta-sts-resolver 0.5.1
- postfix-mta-sts-resolver_project postfix-mta-sts-resolver 0.5.1
Exploit prediction
0.86% chance of exploitation in the next 30 days, higher than 58% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 6.9 | CVSS:3.1/AV:L/AC:H/PR:H/UI:R/S:C/C:H/I:H/A:N |
| NVD | 3.1 | 5.9 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H |
| NVD | 2.0 | 4.3 | AV:N/AC:M/Au:N/C:N/I:N/A:P |
| GitHub | 3.1 | 6.9 | CVSS:3.1/AV:L/AC:H/PR:H/UI:R/S:C/C:H/I:H/A:N |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| pypi | postfix-mta-sts-resolver | <0.5.1 |
0.5.1 |
Affected products
- Snawoot postfix-mta-sts-resolver
Classification
- Weakness
-
- CWE-757 Selection of Less-Secure Algorithm During Negotiation
References
-
github.com
/Snawoot/postfix-mta-sts-resolver/security/advisories/GHSA-h92m-42h4-82f6
web, patch, third-party-advisory, advisory
-
gist.github.com
/Snawoot/b9da85d6b26dea5460673b29df1adc6b
web, patch, third-party-advisory
-
nvd.nist.gov
/vuln/detail/CVE-2019-16791
advisory
-
github.com
/Snawoot/postfix-mta-sts-resolver
package
-
github.com
/pypa/advisory-database/tree/main/vulns/postfix-mta-sts-resolver/PYSEC-2020-174.yaml
web
Sources
- CVE List CVE-2019-16791
- GitHub Advisory GHSA-h92m-42h4-82f6
- NVD CVE-2019-16791
- OSV PYSEC-2020-174
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.