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CVE-2026-90467

CVE-2026-90467 · aiosmtplib before 5.1.3 ESMTP Parameter Injection via unvalidated addresses

This page contains facts from public vulnerability sources. Check the original advisory before updating.

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 6.3 · Medium · EPSS 0.4% · Fix available

Published
Updated

Stack: system

Affected products and versions

  • aiosmtplib

    Versions
    • ≥ 0, < 5.1.3: Affected (semver)
    • 5.1.3: Not affected (semver)

    Update to 5.1.3

  • aiosmtplib Debian:12

    Versions
    • 2.0.0-1
    • 3.0.1-1
    • 3.0.2-1
    • 3.0.2-2
    • 4.0.0-1
    • 4.0.1-1
    • 4.0.1-1~exp1
    • 4.0.2-1
    • 5.0.0-1
    • 5.1.0-1
    • 5.1.0-2
    • 5.1.0-3
    • 5.1.2-1
    • 5.1.3-1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • aiosmtplib Debian:13

    Versions
    • 4.0.0-1
    • 4.0.1-1
    • 4.0.1-1~exp1
    • 4.0.2-1
    • 5.0.0-1
    • 5.1.0-1
    • 5.1.0-2
    • 5.1.0-3
    • 5.1.2-1
    • 5.1.3-1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • aiosmtplib Debian:14

    Versions
    • 4.0.0-1
    • 4.0.1-1
    • 4.0.1-1~exp1
    • 4.0.2-1
    • 5.0.0-1
    • 5.1.0-1
    • 5.1.0-2
    • 5.1.0-3
    • 5.1.2-1
    Affected ranges
    • ECOSYSTEM: < 5.1.3-1

    Update to 5.1.3-1

  • aiosmtplib Ubuntu:22.04:LTS

    Versions
    • 1.1.4-1
    • 1.1.4-2
    • 1.1.6-1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • aiosmtplib Ubuntu:26.10

    Versions
    • 5.1.0-1
    • 5.1.0-3
    • 5.1.2-1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • aiosmtplib Ubuntu:26.04:LTS

    Versions
    • 4.0.0-1
    • 4.0.2-1
    • 5.0.0-1
    • 5.1.0-1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

Original sources

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