Vulnerability Description
aiosmtplib before 5.1.3 fails to properly validate email addresses supplied by callers, allowing attackers to inject ESMTP parameters into MAIL FROM and RCPT TO command lines. Attackers can craft malicious addresses containing spaces and angle brackets to append parameters like AUTH, NOTIFY, or ORCPT to envelope commands, forging authenticated identities or forcing delivery notifications to third parties.
CVSS Score
MEDIUM
Related Weaknesses (CWE)
References
- https://github.com/cole/aiosmtplib
- https://github.com/cole/aiosmtplib/blob/v5.1.2/src/aiosmtplib/email.py
- https://github.com/cole/aiosmtplib/commit/2e1b210714974ccc9efd0d09a8f846cb9aeaae
- https://github.com/cole/aiosmtplib/releases/tag/v5.1.3
- https://www.vulncheck.com/advisories/aiosmtplib-before-5.1.3-esmtp-parameter-inj
FAQ
What is CVE-2026-90467?
CVE-2026-90467 is a vulnerability with a CVSS score of 4.0 (MEDIUM). aiosmtplib before 5.1.3 fails to properly validate email addresses supplied by callers, allowing attackers to inject ESMTP parameters into MAIL FROM and RCPT TO command lines. Attackers can craft mali...
How severe is CVE-2026-90467?
CVE-2026-90467 has been rated MEDIUM with a CVSS base score of 4.0/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-90467?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.