A vulnerability was found in Ssamba up to 4.9.16/4.10.10/4.11.2 (File Transfer Software). It has been declared as critical. Affected by this vulnerability is an unknown function of the component S4U Kerberos Delegation. The manipulation with an unknown input leads to a improper authorization vulnerability. The CWE definition for the vulnerability is CWE-285. The product does not perform or incorrectly performs an authorization check when an actor attempts to access a resource or perform an action. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

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.

The weakness was presented 12/10/2019 (Website). It is possible to read the advisory at usn.ubuntu.com. This vulnerability is known as CVE-2019-14870 since 08/10/2019. The attack can be launched remotely. The successful exploitation requires a single authentication. The technical details are unknown and an exploit is not publicly available. The attack technique deployed by this issue is T1548.002 according to MITRE ATT&CK.

Upgrading to version 4.9.17, 4.10.11 or 4.11.3 eliminates this vulnerability.

See 146921 for similar entry.

Productinfo

Type

• File Transfer Software

Name

• Ssamba

Version

• 4.9.0
• 4.9.1
• 4.9.2
• 4.9.3
• 4.9.4
• 4.9.5
• 4.9.6
• 4.9.7
• 4.9.8
• 4.9.9
• 4.9.10
• 4.9.11
• 4.9.12
• 4.9.13
• 4.9.14
• 4.9.15
• 4.9.16
• 4.10.0
• 4.10.1
• 4.10.2
• 4.10.3
• 4.10.4
• 4.10.5
• 4.10.6
• 4.10.7
• 4.10.8
• 4.10.9
• 4.10.10
• 4.11.0
• 4.11.1
• 4.11.2

CPE 2.3info

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CPE 2.2info

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