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Findings

CVE-2020-7247

OpenSMTPD Remote Code Execution Vulnerability

Published Jan 29, 2020 · updated Jun 16, 2026 · openbsd opensmtpd

smtp_mailaddr in smtp_session.c in OpenSMTPD 6.6, as used in OpenBSD 6.6 and other products, allows remote attackers to execute arbitrary commands as root via a crafted SMTP session, as demonstrated by shell metacharacters in a MAIL FROM field. This affects the "uncommented" default configuration. The issue exists because of an incorrect return value upon failure of input validation.

Code

The project this record applies to. Exploit listings stay in References.

No public source repository is identified for this product.

Timeline

Detection, updates, and resolution for this record.

  1. Jan 29, 2020 · Catalog

    Detected

    smtp_mailaddr in smtp_session.c in OpenSMTPD 6.6, as used in OpenBSD 6.6 and other products, allows remote attackers to execute arbitrary commands as root via a crafted SMTP session, as demonstrated by shell metacharacters in a MAIL FROM field. This affects the "uncommented" default configuration. The issue exists because of an incorrect return value upon failure of input validation.

  2. Mar 25, 2022 · CISA KEV

    Known exploited

    Apply updates per vendor instructions.

  3. Apr 15, 2022 · CISA KEV

    Remediation due

    Apply updates per vendor instructions.

  4. Jun 16, 2026 · Catalog

    Updated

    smtp_mailaddr in smtp_session.c in OpenSMTPD 6.6, as used in OpenBSD 6.6 and other products, allows remote attackers to execute arbitrary commands as root via a crafted SMTP session, as demonstrated by shell metacharacters in a MAIL FROM field. This affects the "uncommented" default configuration. The issue exists because of an incorrect return value upon failure of input validation.

Required action

Apply updates per vendor instructions.

CISA due date Apr 15, 2022

Affected

  • cpe canonical/ubuntu linux18.04
  • cpe canonical/ubuntu linux19.10
  • cpe debian/debian linux10.0
  • cpe debian/debian linux9.0
  • cpe fedoraproject/fedora32
  • cpe openbsd/opensmtpd6.6
  • vendor OpenBSD OpenSMTPDversion unspecified

Sources

  • CISA KEVConfirmed exploitationCVE-2020-7247

    smtp_mailaddr in smtp_session.c in OpenSMTPD, as used in OpenBSD and other products, allows remote attackers to execute arbitrary commands as root via a crafted SMTP session.

    cisa.gov
  • CVE.orgVulnerability recordCVE-2020-7247

    Official CVE identifier

    cve.org
  • FIRST EPSSExploitation probabilityCVE-2020-7247

    30-day exploitation probability 99.0%

    first.org
  • Exploit DatabasePublic exploit reference47984

    Public archive entry. The exploit body is not stored here.

    exploit-db.com
  • Exploit DatabasePublic exploit reference48038

    Public archive entry. The exploit body is not stored here.

    exploit-db.com
  • Exploit DatabasePublic exploit reference48051

    Public archive entry. The exploit body is not stored here.

    exploit-db.com
  • Metasploit ModulesPublic exploit moduleexploit_unix/smtp/opensmtpd_mail_from_rce

    Public module reference (excellent). Module source is not copied into this catalog.

    rapid7.com
  • NIST NVDVulnerability recordCVE-2020-7247

    smtp_mailaddr in smtp_session.c in OpenSMTPD 6.6, as used in OpenBSD 6.6 and other products, allows remote attackers to execute arbitrary commands as root via a crafted SMTP session, as demonstrated by shell metacharacters in a MAIL FROM field. This affects the "uncommented" defa

    nvd.nist.gov
  • Packet Storm SecurityCited referencehttp://packetstormsecurity.com/files/156137/OpenBSD-OpenSMTPD-Privilege-Escalation-Code-Execution.html

    Packet Storm link already published on the finding.

    packetstormsecurity.com
  • Packet Storm SecurityCited referencehttp://packetstormsecurity.com/files/156145/OpenSMTPD-6.6.2-Remote-Code-Execution.html

    Packet Storm link already published on the finding.

    packetstormsecurity.com
  • Packet Storm SecurityCited referencehttp://packetstormsecurity.com/files/156249/OpenSMTPD-MAIL-FROM-Remote-Code-Execution.html

    Packet Storm link already published on the finding.

    packetstormsecurity.com
  • Packet Storm SecurityCited referencehttp://packetstormsecurity.com/files/156295/OpenSMTPD-6.6.1-Local-Privilege-Escalation.html

    Packet Storm link already published on the finding.

    packetstormsecurity.com
  • Packet Storm SecurityCited referencehttp://packetstormsecurity.com/files/162093/OpenBSD-OpenSMTPD-6.6-Remote-Code-Execution.html

    Packet Storm link already published on the finding.

    packetstormsecurity.com

References