CVE-2026-90467
Published:September 12, 2026
Updated:September 22, 2026
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.
Affected Packages
aiosmtplib (CONDA):
Affected version(s) >=1.0.2 <5.1.3Fix Suggestion:
Update to version 5.1.3https://github.com/cole/aiosmtplib.git (GITHUB):
Affected version(s) >=v0.1 <v5.1.3Fix Suggestion:
Update to version v5.1.3aiosmtplib (PYTHON):
Affected version(s) >=0.1.2 <5.1.3Fix Suggestion:
Update to version 5.1.3Related Resources (5)
Do you need more information?
Contact UsCVSS v4
Base Score:
6.3
Attack Vector
NETWORK
Attack Complexity
LOW
Attack Requirements
PRESENT
Privileges Required
NONE
User Interaction
NONE
Vulnerable System Confidentiality
NONE
Vulnerable System Integrity
LOW
Vulnerable System Availability
NONE
Subsequent System Confidentiality
NONE
Subsequent System Integrity
LOW
Subsequent System Availability
NONE
CVSS v3
Base Score:
4
Attack Vector
NETWORK
Attack Complexity
HIGH
Privileges Required
NONE
User Interaction
NONE
Scope
CHANGED
Confidentiality
NONE
Integrity
LOW
Availability
NONE
Weakness Type (CWE)
Improper Neutralization of Argument Delimiters in a Command ('Argument Injection')
EPSS
Base Score:
0.23