CVE catalog
CVE-2023-51765
sendmail: CVE-2023-51765
- Severity
- Medium · CVSS 5.3
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N - Published
- Source
- [NVD] · [CVE record]
- EPSS
- 1.08% · Oct 25, 2026
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.
Vulnerable and fixed packages
Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.
| Distribution | Package | Release | Version | Status |
|---|---|---|---|---|
| Debian | sendmail | sid | 8.18.2-2 | fixed |
| Debian | sendmail | forky | 8.18.2-2 | fixed |
| Debian | sendmail | trixie | 8.18.1-6 | fixed |
| Debian | sendmail | bookworm | 8.17.1.9-2+deb12u2 | fixed |
| Ubuntu | sendmail | 14.04 | 8.14.4-2.1ubuntu4 | vulnerable |
| Ubuntu | sendmail | 14.04 | 8.14.4-2.1ubuntu5 | vulnerable |
| Ubuntu | sendmail | 14.04 | 8.14.4-4.1ubuntu1 | vulnerable |
| Ubuntu | sendmail | 14.04 | 8.14.4-4.1ubuntu1.1 | vulnerable |
| Ubuntu | sendmail | 16.04 | 8.14.9-4 | vulnerable |
| Ubuntu | sendmail | 16.04 | 8.15.2-2 | vulnerable |
| Ubuntu | sendmail | 16.04 | 8.15.2-3 | vulnerable |
| Ubuntu | sendmail | 18.04 | 8.15.2-8ubuntu1 | vulnerable |
| Ubuntu | sendmail | 18.04 | 8.15.2-9ubuntu1 | vulnerable |
| Ubuntu | sendmail | 18.04 | 8.15.2-10 | vulnerable |
| Ubuntu | sendmail | 20.04 | 8.15.2-13 | vulnerable |
| Ubuntu | sendmail | 20.04 | 8.15.2-17ubuntu1 | vulnerable |
| Ubuntu | sendmail | 20.04 | 8.15.2-18 | vulnerable |
| Ubuntu | sendmail | 22.04 | 8.15.2-22ubuntu2 | vulnerable |
| Ubuntu | sendmail | 22.04 | 8.15.2-22ubuntu3 | vulnerable |
| Suse | sendmail | linux enterprise module for basesystem 15 sp5 | 8.15.2-150000.8.12.1 | fixed |
| Suse | sendmail | linux enterprise module for package hub 15 sp5 | 8.15.2-150000.8.12.1 | fixed |
| Opensuse | sendmail | leap 15.5 | 8.15.2-150000.8.12.1 | fixed |
| Suse | sendmail | linux enterprise module for legacy 12 | 8.14.9-4.9.1 | fixed |
Fixed-version evidence
| Distribution | Package | Type | Release | Fixed version | Urgency | Origin | Bugs |
|---|---|---|---|---|---|---|---|
| Debian | sendmail | source | sid | 8.18.1-1 | not yet assigned | Not reported | [1059386] |
| Debian | sendmail | source | forky | 8.18.1-1 | not yet assigned | Not reported | [1059386] |
| Debian | sendmail | source | trixie | 8.18.1-1 | not yet assigned | Not reported | [1059386] |
| Debian | sendmail | source | bookworm | 8.17.1.9-2+deb12u1 | not yet assigned | Not reported | [1059386] |
| Suse | sendmail | rpm | linux enterprise module for basesystem 15 sp5 | 8.15.2-150000.8.12.1 | Not reported | SUSE-SU-2024:0743-1 | Not reported |
| Suse | sendmail | rpm | linux enterprise module for package hub 15 sp5 | 8.15.2-150000.8.12.1 | Not reported | SUSE-SU-2024:0743-1 | Not reported |
| Opensuse | sendmail | rpm | leap 15.5 | 8.15.2-150000.8.12.1 | Not reported | SUSE-SU-2024:0743-1 | Not reported |
| Suse | sendmail | rpm | linux enterprise module for legacy 12 | 8.14.9-4.9.1 | Not reported | SUSE-SU-2024:0742-1 | Not reported |
OpenFactory catalog packages
Matching against OpenFactory catalog package versions is in progress.
References
- [https://ftp.suse.com/pub/projects/security/csaf/suse-su-2024_0742-1.json]
- [https://osv.dev/vulnerability/DEBIAN-CVE-2023-51765]
- [https://osv.dev/vulnerability/DLA-3829-1]
- [https://osv.dev/vulnerability/SUSE-SU-2024:0742-1]
- [https://osv.dev/vulnerability/SUSE-SU-2024:0743-1]
- [https://osv.dev/vulnerability/UBUNTU-CVE-2023-51765]
- [https://security-tracker.debian.org/tracker/CVE-2023-51765]
- [https://security.access.redhat.com/data/csaf/v2/vex/2023/cve-2023-51765.json]
- [https://wid.cert-bund.de/.well-known/csaf/white/2023/wid-sec-w-2023-3206.json]
[CERT-Bund public advisories] · [Debian Security Tracker] · [FIRST EPSS] · [OSV Package Vulnerability Database] · [Red Hat security advisories and VEX] · [SUSE security advisories and VEX]