CVE-2026-90467

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 v3 4.0 MEDIUM

4.0^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/cole/aiosmtplib
https://github.com/cole/aiosmtplib/blob/v5.1.2/src/aiosmtplib/email.py
https://github.com/cole/aiosmtplib/commit/2e1b210714974ccc9efd0d09a8f846cb9aeaaec2
https://github.com/cole/aiosmtplib/releases/tag/v5.1.3
https://www.vulncheck.com/advisories/aiosmtplib-before-5.1.3-esmtp-parameter-injection-via-unvalidated-addresses

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-12 02:16

Updated : 2026-09-14 19:17

NVD link : CVE-2026-90467

Mitre link : CVE-2026-90467

CVE.ORG link : CVE-2026-90467

JSON object : View

Products Affected

No product.

CWE

CWE-88

Improper Neutralization of Argument Delimiters in a Command ('Argument Injection')

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