CVE-2023-51765

MEDIUM

sendmail < 8.18.0.2 - SMTP Smuggling via LF.CR.LF Sequence

Title source: llm
STIX 2.1

Description

sendmail through 8.17.2 allows SMTP smuggling in certain configurations. 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 sendmail supports <LF>.<CR><LF> but some other popular e-mail servers do not. This is resolved in 8.18 and later versions with 'o' in srv_features.

References (17)

Core 17
Core References
Issue Tracking, Third Party Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2255869
Issue Tracking, Patch, Third Party Advisory
https://bugzilla.suse.com/show_bug.cgi?id=1218351
Mailing List, Third Party Advisory mailing-list
http://www.openwall.com/lists/oss-security/2023/12/24/1
Mailing List, Third Party Advisory mailing-list
http://www.openwall.com/lists/oss-security/2023/12/25/1
Mailing List, Third Party Advisory mailing-list
http://www.openwall.com/lists/oss-security/2023/12/26/5
Mailing List, Third Party Advisory mailing-list
http://www.openwall.com/lists/oss-security/2023/12/29/5
Mailing List, Third Party Advisory mailing-list
http://www.openwall.com/lists/oss-security/2023/12/30/3
Mailing List, Third Party Advisory mailing-list
http://www.openwall.com/lists/oss-security/2023/12/30/1

Scores

CVSS v3 5.3
EPSS 0.0107
EPSS Percentile 60.4%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

Details

CWE
CWE-345
Status published
Products (4)
freebsd/freebsd < 11.0
redhat/enterprise_linux 8.0
redhat/enterprise_linux 9.0
sendmail/sendmail < 8.18.0.2
Published Dec 24, 2023
Tracked Since Feb 18, 2026