| Name | CVE-2023-51765 |
| 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. |
| Source | CVE (at NVD; CERT, LWN, oss-sec, fulldisc, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more) |
| Debian Bugs | 1059386 |
Vulnerable and fixed packages
The table below lists information on source packages.
| Source Package | Release | Version | Status |
|---|
| sendmail (PTS) | jessie | 8.14.4-8+deb8u2 | vulnerable |
| stretch | 8.15.2-8+deb9u1 | vulnerable |
| buster | 8.15.2-14~deb10u1 | vulnerable |
| bullseye | 8.15.2-22 | vulnerable |
| bookworm | 8.17.1.9-2 | vulnerable |
| trixie | 8.18.1-1 | fixed |
| sid | 8.18.1-2 | fixed |
The information below is based on the following data on fixed versions.
| Package | Type | Release | Fixed Version | Urgency | Origin | Debian Bugs |
|---|
| sendmail | source | jessie | (unfixed) | end-of-life | | |
| sendmail | source | (unstable) | 8.18.1-1 | | | 1059386 |
Notes
[bookworm] - sendmail <no-dsa> (Minor issue)
[bullseye] - sendmail <no-dsa> (Minor issue)
https://sec-consult.com/blog/detail/smtp-smuggling-spoofing-e-mails-worldwide/
https://www.openwall.com/lists/oss-security/2023/12/21/6
https://www.openwall.com/lists/oss-security/2023/12/26/5