CVE-2023-51764 describes an SMTP smuggling vulnerability in Postfix versions through 3.8.5, allowing remote attackers to inject email messages with spoofed sender addresses, bypassing SPF. This affects various Postfix distributions including Fedora and Red Hat Enterprise Linux. The vulnerability has a CVSS score of 5.3 (Medium), indicating a network-based attack with low complexity and a low impact on integrity. There is currently no evidence of active exploitation, public exploit code (Metasploit, Nuclei, ExploitDB), or significant community discussion or media coverage.
| Vendor | Product | Version(s) | CPE |
|---|---|---|---|
< 3.5.23CPE matchmatch criteria | cpe:2.3:a:postfix:postfix:*:*:*:*:*:*:*:* | ||
>= 3.6.0, < 3.6.13CPE matchmatch criteria | cpe:2.3:a:postfix:postfix:*:*:*:*:*:*:*:* | ||
>= 3.7.0, < 3.7.9CPE matchmatch criteria | cpe:2.3:a:postfix:postfix:*:*:*:*:*:*:*:* | ||
>= 3.8.0, < 3.8.4CPE matchmatch criteria | cpe:2.3:a:postfix:postfix:*:*:*:*:*:*:*:* | ||
38CPE matchmatch criteria | cpe:2.3:o:fedoraproject:fedora:38:*:*:*:*:*:*:* |
CVSS version used by this source: 3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
The average CVE in this peer group has 0.0 Twitter, 0.0 Reddit, 0.1 Bluesky, 0.0 Mastodon, and 0.4 GitHub mentions.
No media coverage found for this CVE.
The average CVE in this peer group has 0.0 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.
CVE-2023-51764
Jun 11, 2024postfix: SMTP smuggling vulnerability
Dec 18, 2023Postfix 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.
Dec 12, 2023