CVE-2026-90467aiosmtplib before 5.1.3 ESMTP Parameter Injection via unvalidated addresses
Updated under an hour ago ()
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It affects cole aiosmtplib. Add what you run to find out whether that includes you.
No exploitation reported and no EPSS estimate yet.
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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
- 4.0 MEDIUM (v3.1, CNA)CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:L/A:N
- Weakness (CWE)
- CWE-88
- Known exploited
- Not in CISA's KEV catalog
- EPSS (exploitation in the next 30 days)
- Not loaded for this CVE
- Assigned by
- VulnCheck
- NVD analysis
- Deferred
- Record last updated
- Sep 14, 2026
- First seen by InfoSec Signals
- Oct 9, 2026
Affected products
cole aiosmtplib cole:aiosmtplib (from the name) | before 5.1.3; 5.1.3 not affected | CNA record |
References
- https://github.com/cole/aiosmtplib/commit/2e1b210714974ccc9efd0d09a8f846cb9aeaaec2patch
- https://github.com/cole/aiosmtplib/releases/tag/v5.1.3release-notes
- https://github.com/cole/aiosmtplib/blob/v5.1.2/src/aiosmtplib/email.pytechnical-description
- https://github.com/cole/aiosmtplibproduct
- https://www.vulncheck.com/advisories/aiosmtplib-before-5.1.3-esmtp-parameter-injection-via-unvalidated-addressesthird-party-advisory
The CVE record on cve.org NVD's entry
The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.