CVE-2019-14870
moderate-risk
Published 2019-12-10
All Samba versions 4.x.x before 4.9.17, 4.10.x before 4.10.11 and 4.11.x before 4.11.3 have an issue, where the S4U (MS-SFU) Kerberos delegation model includes a feature allowing for a subset of clients to be opted out of constrained delegation in any way, either S4U2Self or regular Kerberos authentication, by forcing all tickets for these clients to be non-forwardable. In AD this is implemented by a user attribute delegation_not_allowed (aka not-delegated), which translates to disallow-forwardable. However the Samba AD DC does not do that for S4U2Self and does set the forwardable flag even if the impersonated client has the not-delegated flag set.
Do I need to act?
~
4.7% chance of exploitation in next 30 days
EPSS score — moderate exploit probability
-
Not on CISA KEV list
No confirmed active exploitation reported to CISA
?
Patch status unknown
Check vendor advisories for fix availability and mitigation guidance
5
CVSS 5.4/10
Medium
NETWORK
/ LOW complexity
Affected Products (11)
Affected Vendors
References (28)
Issue Tracking
https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2019-14870
Third Party Advisory
https://security.gentoo.org/glsa/202003-52
Third Party Advisory
https://security.netapp.com/advisory/ntap-20191210-0002/
Third Party Advisory
https://usn.ubuntu.com/4217-1/
Third Party Advisory
https://usn.ubuntu.com/4217-2/
Vendor Advisory
https://www.samba.org/samba/security/CVE-2019-14870.html
Third Party Advisory
https://www.synology.com/security/advisory/Synology_SA_19_40
Issue Tracking
https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2019-14870
and 8 more references
45
/ 100
moderate-risk
Severity
21/34 · High
Exploitability
8/34 · Low
Exposure
16/34 · Moderate