aiosmtpd vulnerable to SMTP smuggling

中 5.3CVE-2024-27305 · GHSA-pr2m-px7j-xg65 · PYSEC-2024-221 · 12/03/2024 公開 · 17/06/2026 更新

要点

CVE-2024-27305 は aiosmtpd, aiosmtpd (aio-libs) に影響する深刻度「中」 (CVSS 5.3) の脆弱性です。
今後30日間に悪用される確率（EPSS）：0.37%（全脆弱性の 31.2% より高い）。
対処：1.4.5 以降に更新してください。

パッケージ	影響を受けるバージョン	修正済みバージョン
aiosmtpd PyPI	`< 1.4.5`	`1.4.5`
aiosmtpd aio-libs	`< 1.4.5`	`1.4.5`

概要

Summary

aiosmtpd is vulnerable to inbound SMTP smuggling. SMTP smuggling is a novel vulnerability based on not so novel interpretation differences of the SMTP protocol. By exploiting SMTP smuggling, an attacker may send smuggle/spoof e-mails with fake sender addresses, allowing advanced phishing attacks. This issue also existed in other SMTP software like Postfix (https://www.postfix.org/smtp-smuggling.html).

Details

Detailed information on SMTP smuggling can be found in the full blog post (https://sec-consult.com/blog/detail/smtp-smuggling-spoofing-e-mails-worldwide/) or on the Postfix homepage (https://www.postfix.org/smtp-smuggling.html). (and soon on the official website https://smtpsmuggling.com/)

Impact

With the right SMTP server constellation, an attacker can send spoofed e-mails to inbound/receiving aiosmtpd instances.

NVD の説明

aiosmtpd is a reimplementation of the Python stdlib smtpd.py based on asyncio. aiosmtpd is vulnerable to inbound SMTP smuggling. SMTP smuggling is a novel vulnerability based on not so novel interpretation differences of the SMTP protocol. By exploiting SMTP smuggling, an attacker may send smuggle/spoof e-mails with fake sender addresses, allowing advanced phishing attacks. This issue is also existed in other SMTP software like Postfix. With the right SMTP server constellation, an attacker can send spoofed e-mails to inbound/receiving aiosmtpd instances. This issue has been addressed in version 1.4.5. Users are advised to upgrade. There are no known workarounds for this vulnerability.