# CVE-2026-90467: aiosmtplib: aiosmtplib before 5.1.3 fails to properly validate email addresses supplied by callers, allowing attackers to inject...

CVE-2026-90467 is fixed in aiosmtplib on 1 platform by DEBIAN-CVE-2026-90467 (version 5.1.3-1), released September 17, 2026. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2026-90467
- Priority: Routine
- CVSS: n/a
- EPSS: 0.0039
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Sep 12, 2026

## 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.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | aiosmtplib Debian 14 | 5.1.3-1 | [DEBIAN-CVE-2026-90467](https://patchblox.com/security/data/fix/linux/debian-cve-2026-90467.md) | Sep 17, 2026 |

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Data as of 2026-11-09T01:18:40Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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