CVE-2026-90467

medium

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.

References

https://www.vulncheck.com/advisories/aiosmtplib-before-5.1.3-esmtp-parameter-injection-via-unvalidated-addresses

https://github.com/cole/aiosmtplib/releases/tag/v5.1.3

https://github.com/cole/aiosmtplib/commit/2e1b210714974ccc9efd0d09a8f846cb9aeaaec2

https://github.com/cole/aiosmtplib/blob/v5.1.2/src/aiosmtplib/email.py

https://github.com/cole/aiosmtplib

Details

Source: Mitre, NVD

Published: 2026-09-12

Updated: 2026-09-12

Risk Information

CVSS v2

Base Score: 2.6

Vector: CVSS2#AV:N/AC:H/Au:N/C:N/I:P/A:N

Severity: Low

CVSS v3

Base Score: 4

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

Severity: Medium

CVSS v4

Base Score: 6.3

Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:L/SA:N

Severity: Medium

EPSS

EPSS: 0.00229