CVE-2023-5770

Name: CVE-2023-5770
Creator: NVD / NIST
Published: 2024-01-09T22:15:43.4+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 5.4/10EPSS 0.34%

Last modified Jun 17, 2026

CVE-2023-5770 is a medium-severity vulnerability rated 5.4/10 on the CVSS scale. Proofpoint Enterprise Protection contains a vulnerability in the email delivery agent that allows an unauthenticated attacker to inject improperly encoded HTML into the email body of a message through the email subject. The vulnerability is caused by inappropriate encoding when rewriting the email before delivery.This issue affects Proofpoint Enterprise Protection: from 8.20.2 before patch 4809, from 8.20.0 before patch 4805, from 8.18.6 before patch 4804 and all other prior versions. . EPSS estimates a 0.34% chance of exploitation in the next 30 days.

Description

Proofpoint Enterprise Protection contains a vulnerability in the email delivery agent that allows an unauthenticated attacker to inject improperly encoded HTML into the email body of a message through the email subject. The vulnerability is caused by inappropriate encoding when rewriting the email before delivery.This issue affects Proofpoint Enterprise Protection: from 8.20.2 before patch 4809, from 8.20.0 before patch 4805, from 8.18.6 before patch 4804 and all other prior versions.

Metrics

CVSS 3.1

5.4/10

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

EPSS Probability

0.34%

25.8th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Proofpoint	Enterprise Protection	8.18.6
Proofpoint	Enterprise Protection	8.20.0
Proofpoint	Enterprise Protection	8.20.2

References

https://www.proofpoint.com/us/security/security-advisories/pfpt-sa-2023-0009Vendor Advisory
https://www.proofpoint.com/us/security/security-advisories/pfpt-sa-2023-0009Vendor Advisory

Timeline

Published: Jan 9, 2024
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2023-5770?

How severe is CVE-2023-5770?

CVE-2023-5770 has a CVSS score of 5.4/10 (MEDIUM severity). The EPSS model estimates a 0.34% probability of exploitation in the next 30 days.

How do I fix CVE-2023-5770?

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-2023-5770?

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

Scan your code now

Source: NVD / NIST