CVSS 4.0
6.3 mediumCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:L/SA:NCVE-2026-90467
Medium (6.3). EPSS 0.4% chance of exploitation in the next 30 days.
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.
Severity
CVSS 3.1
4.0 mediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:L/A:N- EPSS
- 0.4% chance of exploitation in the next 30 days; higher than 33% of CVEs (scores of 2026-10-31)
- CWE
- CWE-88
- Published
- Modified
- Record from
- the NVD, synced
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/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