CVE-2020-7247
KEVOpenSMTPD Remote Code Execution Vulnerability
Description
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.
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.
CVSS 3.1 vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HPublishedJan 29, 2020
Last modifiedJun 17, 2026
Added to KEVMar 25, 2022
Remediation dueApr 15, 2022
References
- packetstormsecurity.com/files/156137/OpenBSD-OpenSMTPD-Privilege-Escalation-Code-Execution.htmlExploitThird Party Advisory
- packetstormsecurity.com/files/156145/OpenSMTPD-6.6.2-Remote-Code-Execution.htmlExploitThird Party Advisory
- packetstormsecurity.com/files/156249/OpenSMTPD-MAIL-FROM-Remote-Code-Execution.htmlExploitThird Party Advisory
- packetstormsecurity.com/files/156295/OpenSMTPD-6.6.1-Local-Privilege-Escalation.htmlExploitThird Party Advisory
- packetstormsecurity.com/files/162093/OpenBSD-OpenSMTPD-6.6-Remote-Code-Execution.htmlBroken LinkThird Party Advisory
- seclists.org/fulldisclosure/2020/Jan/49ExploitMailing List
- openwall.com/lists/oss-security/2020/01/28/3ExploitMailing List
- github.com/openbsd/src/commit/9dcfda045474d8903224d175907bfc29761dcb45Patch
- lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/OPH4QU4DNVHA7ACFXMYFCEP5PSXXPN4E/Mailing ListThird Party Advisory
- seclists.org/bugtraq/2020/Jan/51Mailing ListThird Party Advisory
- usn.ubuntu.com/4268-1/Third Party Advisory
- debian.org/security/2020/dsa-4611Mailing ListThird Party Advisory
0 recent articles mention this CVE
89
Risk assessment · Critical
Actively exploited. Patch immediately.
- Exploitation
- Confirmed in the wild (CISA KEV)
- Federal remediation deadline
- Overdue by 1655 days
- CVSS
- 9.8 CRITICAL
- EPSS (30-day exploit probability)
- 99.0% · top 1% of all CVEs
- Weakness
- CWE-78
- Attack vector
- Network, remotely reachable
- Preconditions
- No privileges and no user interaction
Recommended actions
- 1.Apply updates per vendor instructions.
- 2.Treat as emergency change: patch or isolate internet-facing instances first.
- 3.Review exposure: confirm which instances are reachable from the internet and restrict access until patched.
- 4.Hunt for compromise: review logs for the disclosure window, not just from the patch date.
Assessment is derived automatically from the live signals above; verify against your own asset inventory.