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.
Attack Parameters
Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Attack Requirements
Present
Additional conditions required
Privileges Required
None
No privileges needed
User Interaction
None
No user interaction needed
Impact Assessment
Confidentiality
None
No data leak
Integrity
Low
Partial data modification
Availability
None
No disruption
CVSS Vector v4.0
Weakness Type (CWE)
Vulnerable Products
cole:aiosmtplib
References 5
https://github.com/cole/aiosmtplib
disclosure@vulncheck.com
https://github.com/cole/aiosmtplib/blob/v5.1.2/src/aiosmtplib/email.py
disclosure@vulncheck.com
https://github.com/cole/aiosmtplib/commit/2e1b210714974ccc9efd0d09a8f846cb9aeaa…
disclosure@vulncheck.com
https://github.com/cole/aiosmtplib/releases/tag/v5.1.3
disclosure@vulncheck.com
https://www.vulncheck.com/advisories/aiosmtplib-before-5.1.3-esmtp-parameter-in…
disclosure@vulncheck.com