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TI-2020-09717 Aliases CVE-2020-12063GHSA-5wj2-9pm2-74vm

A certain Postfix 2.10.1-7 package could allow an attacker to send an email from an…

Priority LOW 26Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
None · Low · None
Fix status
No fix listed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA.

Summary

A certain Postfix 2.10.1-7 package could allow an attacker to send an email from an arbitrary-looking sender via a homoglyph attack, as demonstrated by the similarity of \xce\xbf to the 'o' character. This is potentially relevant when the /etc/postfix/sender_login feature is used, because a spoofed outbound message that uses a configured sender address is blocked with a "Sender address rejected: not logged in" error message, but a spoofed outbound message that uses a homoglyph of a configured sender address is not blocked. NOTE: some third parties argue that any missed blocking of spoofed outbound messages - except for exact matches to a sender address in the /etc/postfix/sender_login file - is outside the design goals of Postfix and thus cannot be considered a Postfix vulnerability

Why it matters now

EPSS 0.00935 60th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix No fix listed No fixed version in the sources yet

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
——all versions—No fix listedCNA
  • — Vendor— Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:postfix:postfix:2.10.1:*:*:*:*:*:*:*2.10.1VulnerablePostfix
  • cpe:2.3:a:postfix:postfix:2.10.1:*:*:*:*:*:*:* Versions 2.10.1 Vulnerable ·Postfix

Remediation

No fixed version listed by the sources yet.

Vendor assessments

Red Hat

Red Hat's page for this CVE →

Not affected: 4 products
  • Red Hat Enterprise Linux 5
  • Red Hat Enterprise Linux 6
  • Red Hat Enterprise Linux 7
  • Red Hat Enterprise Linux 8

Timeline

  1. 2026-10-02 Threatist record created from CVE-2020-12063
  2. 2026-10-03 Alias added: GHSA-5wj2-9pm2-74vm

References

Exploit 1

Advisory 1

  • TI-2011-01499 The SMTP server in Postfix before 2.5.13, 2.6.x before 2.6.10, 2.7.x before 2.7.4, and… CVSS 2.0MEDIUM 6.8
  • TI-2011-00345 The STARTTLS implementation in Postfix 2.4.x before 2.4.16, 2.5.x before 2.5.12, 2.6.x… CVSS 2.0MEDIUM 6.8
  • TI-2023-28393 Postfix through 3.8.5 allows SMTP smuggling unless configured with… CVSS 3.1MEDIUM 5.3
  • TI-2017-07491 Postfix before 2.11.10, 3.0.x before 3.0.10, 3.1.x before 3.1.6, and 3.2.x before 3.2.2… CVSS 3.0HIGH 7.8
  • TI-2026-32009 Postfix before 3.8.16, 3.9 before 3.9.10, and 3.10 before 3.10.9 sometimes allows a… CVSS 3.1HIGH 7.5
  • TI-2012-00748 Multiple SQL injection vulnerabilities in Postfix Admin (aka postfixadmin) before 2.3.5… CVSS 2.0MEDIUM 6.5
See all 11 →

Sources

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