OpenSMTPD Remote Code Execution Vulnerability

Are you affected?

Enter the version you run. The result uses only the ranges stored on this record.

The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.

• 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

How to fix CVE-2020-7247

• Recommended remediation

  Apply updates per vendor instructions. CISA due date Apr 15, 2022.

• Official advisories

  • CISA KEV · cisa.gov
  • CVE.org · cve.org
  • FIRST EPSS · first.org
  • NIST NVD · nvd.nist.gov
  • Packet Storm Security · packetstormsecurity.com
  • Packet Storm Security · packetstormsecurity.com

What to do

Three questions, each answered from this record only. Confirm the vendor advisory before you patch.

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.

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
• VulnCheck 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.

  vulncheck.com

References

• Exploit · packetstormsecurity.com
• Exploit · packetstormsecurity.com
• Exploit · packetstormsecurity.com
• Exploit · packetstormsecurity.com
• Broken Link · packetstormsecurity.com
• Exploit · seclists.org
• CISA note · nvd.nist.gov
• VulnCheck exploitation evidence · cisa.gov
• Patch · openbsd.org

Freshness

Last verified in this catalog Oct 17, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.