CVE-2024-27305: aiosmtpd — Fix

Description

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.

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CVSS v3.1 Score

5.3

MEDIUM

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

Weakness Type (CWE)

CWE-345 CWE-345

Affected Products

Vendor	Product	Versions
aio-libs	aiosmtpd	< 1.4.5

References

Advisories & Patches

https://github.com/aio-libs/aiosmtpd/commit/24b6c79c8921cf1800e27ca144f4f37023982bbb https://github.com/aio-libs/aiosmtpd/security/advisories/GHSA-pr2m-px7j-xg65 https://github.com/aio-libs/aiosmtpd/commit/24b6c79c8921cf1800e27ca144f4f37023982bbb https://github.com/aio-libs/aiosmtpd/security/advisories/GHSA-pr2m-px7j-xg65

Other References

https://www.postfix.org/smtp-smuggling.html https://www.postfix.org/smtp-smuggling.html

Frequently Asked Questions

What is CVE-2024-27305? +

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. It has a CVSS v3.1 base score of 5.3 (MEDIUM).

How severe is CVE-2024-27305? +

CVE-2024-27305 has a CVSS v3.1 score of 5.3 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2024-27305? +

CVE-2024-27305 affects products from aio-libs, specifically: aiosmtpd. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2024-27305? +

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.

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