SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2019-14870

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…

MEDIUM 5.4EPSS 2.78%

Does this matter?

Lower severity and a low EPSS score (2.78%). Track it; it rarely justifies an emergency change on its own.

Description

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.

CVSS 3.1
5.4 MEDIUMCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
EPSS
2.78% probability · 86th percentile
CISA KEV
Not listed
Weakness
CWE-285, CWE-287
Affected
samba/samba · fedoraproject/fedora · canonical/ubuntu linux · debian/debian linux · opensuse/leap
Source
secalert@redhat.com

References

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.