CVE-2023-51764 (GCVE-0-2023-51764)
Vulnerability from cvelistv5
Published
2023-12-24 00:00
Modified
2026-10-08 21:03
Severity ?
CWE
  • n/a
Summary
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 recent versions). Remote attackers can use a published exploitation technique to inject e-mail messages with a spoofed MAIL FROM address, allowing bypass of an SPF protection mechanism. This occurs because Postfix supports <LF>.<CR><LF> but some other popular e-mail servers do not. To prevent attack variants (by always disallowing <LF> without <CR>), a different solution is required, such as the smtpd_forbid_bare_newline=yes option with a Postfix minimum version of 3.5.23, 3.6.13, 3.7.9, 3.8.4, or 3.9.
References
Impacted products
Vendor Product Version
n/a n/a Version: n/a
Show details on NVD website

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