Vulnerability in FreeBSD
CVE-2023-51765
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.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N.
EPSS exploit prediction
EPSS: 0.011 (63.8th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 64th percentile — 63.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.011 · newest: 0.011 · change: 0.000
Affected products
- FreeBSD
- Sendmail
- Red Hat Enterprise Linux — versions 8.0, 9.0
Weakness classification (CWE)
Public proof-of-concept exploits
References
- sec-consult.com/blog/detail/smtp-smuggling-spoofing-e-mails-worldwide/ (Technical Description, Third Party Advisory)
- www.openwall.com/lists/oss-security/2023/12/22/7 (Mailing List, Third Party Advisory)
- www.openwall.com/lists/oss-security/2023/12/21/7 (Mailing List, Third Party Advisory)
- github.com/freebsd/freebsd-src/commit/5dd76dd0cc19450133aa379ce0ce4a68ae07fb39 (Patch)
- www.openwall.com/lists/oss-security/2023/12/24/1 (mailing-list, Mailing List, Third Party Advisory)
- www.openwall.com/lists/oss-security/2023/12/25/1 (mailing-list, Mailing List, Third Party Advisory)
- bugzilla.suse.com/show_bug.cgi (Patch, Third Party Advisory, Issue Tracking)
- bugzilla.redhat.com/show_bug.cgi (Third Party Advisory, Issue Tracking)
- access.redhat.com/security/cve/CVE-2023-51765 (Third Party Advisory)
- fahrplan.events.ccc.de/congress/2023/fahrplan/events/11782.html (Technical Description)
Frequently asked questions
- What is CVE-2023-51765?
- CVE-2023-51765 is a medium-severity vulnerability in FreeBSD, classified under Insufficient Verification of Data Authenticity. CVSS score: 5.3/10. Published 2023-12-24.
- How severe is CVE-2023-51765?
- Medium severity. CVSS v3 base score is 5.3 out of 10.
- Is CVE-2023-51765 known to be exploited?
- 4 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.