CVE-2019-20634

Name: CVE-2019-20634
Creator: NVD / NIST
Published: 2020-03-30T21:15:12.373+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

LOWCVSS 3.7/10EPSS 1.57%

Last modified Jun 17, 2026

CVE-2019-20634 is a low-severity vulnerability rated 3.7/10 on the CVSS scale. An issue was discovered in Proofpoint Email Protection through 2019-09-08. By collecting scores from Proofpoint email headers, it is possible to build a copy-cat Machine Learning Classification model and extract insights from this model. EPSS estimates a 1.57% chance of exploitation in the next 30 days.

Description

An issue was discovered in Proofpoint Email Protection through 2019-09-08. By collecting scores from Proofpoint email headers, it is possible to build a copy-cat Machine Learning Classification model and extract insights from this model. The insights gathered allow an attacker to craft emails that receive preferable scores, with a goal of delivering malicious emails.

Metrics

CVSS 3.1

3.7/10

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N

EPSS Probability

1.57%

72.3th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-697

Affected Software

Vendor	Product	Versions
Proofpoint	Email Protection	<= 2019-09-08

References

https://github.com/moohax/Proof-PuddingThird Party Advisory
https://github.com/moohax/Talks/blob/master/slides/DerbyCon19.pdfThird Party Advisory
https://www.proofpoint.com/us/security/CVE-2019-20634Vendor Advisory
https://www.proofpoint.com/us/security/security-advisories/pfpt-sn-2020-0001Vendor Advisory
https://atlas.mitre.org/studies/AML.CS0008
https://github.com/moohax/Proof-PuddingThird Party Advisory
https://github.com/moohax/Talks/blob/master/slides/DerbyCon19.pdfThird Party Advisory
https://www.proofpoint.com/us/security/CVE-2019-20634Vendor Advisory
https://www.proofpoint.com/us/security/security-advisories/pfpt-sn-2020-0001Vendor Advisory

Timeline

Published: Mar 30, 2020
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2019-20634?

How severe is CVE-2019-20634?

CVE-2019-20634 has a CVSS score of 3.7/10 (LOW severity). The EPSS model estimates a 1.57% probability of exploitation in the next 30 days.

How do I fix CVE-2019-20634?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2019-20634?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST