CVE intelligence

CVE-2023-27043

Vulnerability intelligence

Published Apr 19, 2023Sources checked Oct 29, 2026

5.3MEDIUMCVSS out of 10

What this means

Review the available evidence

CVE-2023-27043 and is rated Medium severity with a CVSS score of 5.3. It is not in the current CISA KEV record we collected. That does not prove exploitation has not occurred.

What to do next

Remediation and response

Microsoft Security Response Center guidance

Vendor revision: Oct 28, 2026

CBL-Mariner Releases

Vendor-listed releases

3.12.3-6
3.9.19-9
3.12.0-1

CISA KEVNot listedBased on the latest collected catalog

EPSS2.5%Estimated 30-day exploitation probability

Ransomware useNot markedCISA KEV ransomware field

Threat actors0Source-linked actor relationships

Overview

What is CVE-2023-27043?

The email module of Python through 3.11.3 incorrectly parses e-mail addresses that contain a special character. The wrong portion of an RFC2822 header is identified as the value of the addr-spec.

In some applications, an attacker can bypass a protection mechanism in which application access is granted only after verifying receipt of e-mail to a specific domain (e.g., only @company.example.com addresses may be used for signup). This occurs in email/_parseaddr.py in recent versions of Python.

Source: NVD