Is Postfix 2.11.11 affected?

EOL

2 known vulnerabilities affect 2.11.11 (highest CVSS 5.3).

Your branch 2.11 has reached end of life (Feb 21, 2018).

12 newer releases in its track, up to 3.11.7. What changed up to 3.11.7

Vulnerabilities affecting 2.11.11

5.3
CVE-2023-51764 Postfix through 3.8.5 allows SMTP smuggling unless configured with smtpd_data_restrictions=reject_unauth_pipelining and smtpd_discard_ehlo_keywords=chunking (or certain other options that exist in… fixed in 3.5.23
3.7
CVE-2026-43964 Postfix before 3.8.16, 3.9 before 3.9.10, and 3.10 before 3.10.9 sometimes allows a buffer over-read and process crash via an enhanced status code that lacks text after the third number. fixed in 3.8.16