CVE-2020-7247: OpenSMTPD Remote Code Execution Vulnerability

Reference page built from the source records below, each shown as its source publishes it. Dataset version ref-b670cdd38e8b, updated 2026-11-02T23:39:54.475Z.

CISA Known Exploited Vulnerabilities

Name
OpenSMTPD Remote Code Execution Vulnerability
Vendor
OpenBSD
Product
OpenSMTPD
Added to the catalog
2022-03-25
Due date for US federal agencies
2022-04-15
Weaknesses
CWE-755, CWE-78
Catalog version
2026.10.30

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.

Required action (CISA)

Apply updates per vendor instructions.

Ransomware use: CISA does not mark known use of this vulnerability in ransomware campaigns.

Links in CISA's notes

Read on 2026-11-02T23:39:54.475Z under licence cisa-kev-cc0@b0067899 from https://www.cisa.gov/sites/default/files/feeds/known_exploited_vulnerabilities.json

NVD analysis

Status
Analyzed
Published
2020-01-29T16:15:12.897
Last modified
2026-06-17T03:24:35.133
Weaknesses
CWE-78, CWE-755

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.

MetricScoreSeverityVectorScored by
CVSS 3.19.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H[email protected] (Primary)
CVSS 3.19.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H134c704f-9b21-4f2e-91b3-4a467353bcc0 (Secondary)
CVSS 2.010HIGHAV:N/AC:L/Au:N/C:C/I:C/A:C[email protected] (Primary)

References

This product uses the NVD API but is not endorsed or certified by the NVD.

Read on 2026-11-02T23:41:43.468Z under licence nvd-api-terms-of-use@ff2a5288 from https://services.nvd.nist.gov/rest/json/cves/2.0?cveId=CVE-2020-7247

CVE record

Assigner
mitre
State
PUBLISHED
Published
2020-01-29T15:53:18.000Z
Updated
2025-10-21T23:35:53.008Z
Problem types
n/a

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.

References

Read on 2026-11-03T01:04:58.154Z under licence cve-terms-of-use@81bfa2f3 from https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2020/7xxx/CVE-2020-7247.json

Defensive techniques (MITRE D3FEND)

D3FEND maps these defensive techniques to the weakness (CWE) that NVD lists for this CVE, through the digital artifacts the weakness affects. D3FEND does not say they stop this vulnerability.

CWE-78: Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')

D3FEND ontology version 1.6.0.

Read on 2026-11-02T23:54:16.526Z under licence d3fend-terms-of-use@f98cbc7e from https://d3fend.mitre.org/api/weakness/cwe/CWE-78.json

CWE-755: Improper Handling of Exceptional Conditions

D3FEND lists no defensive technique for this weakness.

D3FEND ontology version 1.6.0.

Read on 2026-11-03T00:02:48.486Z under licence d3fend-terms-of-use@f98cbc7e from https://d3fend.mitre.org/api/weakness/cwe/CWE-755.json

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"The MITRE Corporation (MITRE) hereby grants you a non-exclusive, royalty-free license to use D3FEND for research, development, and commercial purposes. Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy." Terms: https://d3fend.mitre.org/tou/

Sources and licences

  • CISA

    Source: CISA Catalog of Known Exploited Vulnerabilities, version 2026.10.30, CC0 1.0. Use of this data does not imply endorsement by CISA or DHS.

    CC0 1.0 Universal

  • National Vulnerability Database (NIST)

    This product uses the NVD API but is not endorsed or certified by the NVD.

    NVD API Terms of Use (NIST publications in the public domain, 17 U.S.C. 105)

  • CVE Program, The MITRE Corporation

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    CVE Program Terms of Use ("CVE Usage" licence)

  • MITRE D3FEND

    MITRE D3FEND™ knowledge graph. © 2025 The MITRE Corporation.
    "The MITRE Corporation (MITRE) hereby grants you a non-exclusive, royalty-free license to use D3FEND for research, development, and commercial purposes. Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy." Terms: https://d3fend.mitre.org/tou/

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Cite this page

Dragons Eye Ransomware Tracker, "CVE-2020-7247: OpenSMTPD Remote Code Execution Vulnerability",
entity page, dataset version ref-b670cdd38e8b, updated 2026-11-02T23:39:54.475Z,
https://ransomware-tracker.com/cve/CVE-2020-7247 (accessed 2026-11-03).
Underlying source: CISA Catalog of Known Exploited Vulnerabilities, version 2026.10.30.
Underlying source: National Vulnerability Database (NIST), CVE API 2.0, record last modified 2026-06-17T03:24:35.133.
Underlying source: CVE List (CVE Program, The MITRE Corporation), record updated 2025-10-21T23:35:53.008Z.
Underlying source: MITRE D3FEND, ontology version 1.6.0.

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CISA KEV index