CVEvulnerability

CVE-2020-7247

9.8 CRITICAL Known exploited Published 2020-01-29 Modified 2026-06-17 Official page ↗

CISA Known Exploited Vulnerability

OpenSMTPD Remote Code Execution Vulnerability — OpenBSD OpenSMTPD

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.

Added to KEV
2022-03-25
Remediation due
2022-04-15
Ransomware use
Unknown
Required action
Apply updates per vendor instructions.
Notes
https://nvd.nist.gov/vuln/detail/CVE-2020-7247
Status
Analyzed
Published
2020-01-29
Last modified
2026-06-17
Assigner
[email protected]
CVSS 3.1 ([email protected])
9.8 CRITICAL — CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS 3.1 (134c704f-9b21-4f2e-91b3-4a467353bcc0)
9.8 CRITICAL — CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS 2.0 ([email protected])
10.0 HIGH — AV:N/AC:L/Au:N/C:C/I:C/A:C
Weaknesses
CWE-755, CWE-78

Description

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.

Affected configurations

• openbsd opensmtpd 6.6 • debian debian linux 9.0 • debian debian linux 10.0 • fedoraproject fedora 32 • canonical ubuntu linux 18.04 • canonical ubuntu linux 19.10

Related

Weakness · CWE (2)

  • CWE-755 Improper Handling of Exceptional Conditions weakness
  • CWE-78 Improper Neutralization of Special Elements used in an OS Command weakness

References