What’s Vulnerable › Vulnerabilities

CVE-2023-27043

• Severity: medium (CVSS 5.3 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 2.5% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2023-04-19 · updated 2026-06-17
• Weakness: CWE-20

Description

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.

Affected products

• Fedoraproject Fedora: 38, 39
• Active IQ Unified Manager for VMware vSphere, Linux, and Microsoft Windows: all versions
• NetApp ONTAP Select Deploy administration utility: all versions
• Python: through 2.7.18; from 3.0 before 3.8.20; from 3.9.0 before 3.9.20; from 3.10.0 before 3.10.15; from 3.11.0 before 3.11.10; from 3.12.0 before 3.12.6 — fixed in 3.10.15, 3.11.10, 3.12.6, 3.8.20, 3.9.20

How to fix

Upgrade to a fixed version: Python 3.10.15, 3.11.10, 3.12.6, 3.8.20. Check the vendor advisory for mitigations.

References

• http://python.org
• https://github.com/python/cpython/issues/102988
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4ZAEFSFZDNBNJPNOUTLG5COISGQDLMGV/
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/75DTHSTNOFFNAWHXKMDXS7EJWC6W2FUC/
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ARI7VDSNTQVXRQFM6IK5GSSLEIYV4VZH/
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BQAKLUJMHFGVBRDPEY57BJGNCE5UUPHW/
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/HXYVPEZUA3465AEFX5JVFVP7KIFZMF3N/
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/N6M5I6OQHJABNEYY555HUMMKX3Y4P25Z/
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/NEUNZSZ3CVSM2QWVYH3N2XGOCDWNYUA3/
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ORLXS5YTKN65E2Q2NWKXMFS5FWQHRNZW/
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/P2MAICLFDDO3QVNHTZ2OCERZQ34R2PIC/
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/P2W2BZQIHMCKRI5FNBJERFYMS5PK6TAH/

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