CVE-2024-34083 (CVSS 5.4)

Description

aiosmptd is a reimplementation of the Python stdlib smtpd.py based on asyncio. Prior to version 1.4.6, servers based on aiosmtpd accept extra unencrypted commands after STARTTLS, treating them as if they came from inside the encrypted connection. This could be exploited by a man-in-the-middle attack. Version 1.4.6 contains a patch for the issue.

Is your site exposed to CVE-2024-34083?

Run a free security scan — no signup, results in seconds.

CVSS v3.1 Score

5.4

MEDIUM

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

Weakness Type (CWE)

CWE-349 CWE-349

References

Other References

https://github.com/aio-libs/aiosmtpd/commit/b3a4a2c6ecfd228856a20d637dc383541fcdbfda https://github.com/aio-libs/aiosmtpd/security/advisories/GHSA-wgjv-9j3q-jhg8 https://nostarttls.secvuln.info https://github.com/aio-libs/aiosmtpd/commit/b3a4a2c6ecfd228856a20d637dc383541fcdbfda https://github.com/aio-libs/aiosmtpd/security/advisories/GHSA-wgjv-9j3q-jhg8 https://nostarttls.secvuln.info

Frequently Asked Questions

What is CVE-2024-34083? +

aiosmptd is a reimplementation of the Python stdlib smtpd.py based on asyncio. Prior to version 1.4.6, servers based on aiosmtpd accept extra unencrypted commands after STARTTLS, treating them as if they came from inside the encrypted connection. This could be exploited by a man-in-the-middle attack. Version 1.4.6 contains a patch for the issue. It has a CVSS v3.1 base score of 5.4 (MEDIUM).

How severe is CVE-2024-34083? +

CVE-2024-34083 has a CVSS v3.1 score of 5.4 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

How do I check if I'm vulnerable to CVE-2024-34083? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

Related Vulnerabilities

CVE-2025-5994

A multi-vendor cache poisoning vulnerability named 'Rebirthday Attack' has been discovered in caching resolvers that support EDNS Client Subnet (ECS). …

CVE-2025-11411

NLnet Labs Unbound up to and including version 1.24.1 is vulnerable to possible domain hijack attacks. Promiscuous NS RRSets that …

CVE-2025-1680

An acceptance of extraneous untrusted data with trusted data vulnerability has been identified in Moxa’s Ethernet switches, which allows attackers …

CVE-2026-42960 10.0

NLnet Labs Unbound up to and including version 1.25.0 is vulnerable to poisoning via promiscuous records for the authority section. …

CVE-2026-41120 9.8

Dell Wyse Management Suite, versions prior to WMS 5.5 HF1, contain an Acceptance of Extraneous Untrusted Data With Trusted Data …

CVE-2026-50252 9.3

In NLnet Labs Unbound 1.4.22 up to and including 1.25.1, UDP source port is randomized and intended to serve as …

CVE-2024-34083