CVE-2020-17049
Kerberos KDC Security Feature Bypass Vulnerability
MEDIUM 6.6
At a glance
- Source
- NVD
- EPSS
- EPSS 13.79 % · percentile 97 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- microsoft
- NVD status
- Modified
Description
A security feature bypass vulnerability exists in the way Key Distribution Center (KDC) determines if a service ticket can be used for delegation via Kerberos Constrained Delegation (KCD). To exploit the vulnerability, a compromised service that is configured to use KCD could tamper with a service ticket that is not valid for delegation to force the KDC to accept it. The update addresses this vulnerability by changing how the KDC validates service tickets used with KCD.
Weaknesses (CWE)
- CWE-863 — Incorrect Authorization
References
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 3.1 | MEDIUM 6.6 | CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C | microsoft |
| CVSS 3.1 | MEDIUM 6.6 | CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H | NVD · secure@microsoft.com (Secondary) |
| CVSS 3.1 | HIGH 7.2 | CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H | NVD · nvd@nist.gov (Secondary) |
| CVSS 2.0 | HIGH 9.0 | AV:N/AC:L/Au:S/C:C/I:C/A:C | NVD · nvd@nist.gov (Primary) |
European references
- ENISA EUVD · EUVD-2020-9005
- GCVE · GCVE-0-2020-17049
CERT-FR advisories
- CERTFR-2020-AVI-738 — Multiples vulnérabilités dans Microsoft Windows · cert.ssi.gouv.fr
Affected configurations (NVD CPE)
cpe:2.3:o:microsoft:windows_server_2012:*:*:*:*:*:*:*:*cpe:2.3:o:microsoft:windows_server_2012:r2:*:*:*:*:*:*:*cpe:2.3:o:microsoft:windows_server_2016:-:*:*:*:*:*:*:*cpe:2.3:o:microsoft:windows_server_2016:20h2:*:*:*:*:*:*:*cpe:2.3:o:microsoft:windows_server_2016:1903:*:*:*:*:*:*:*cpe:2.3:o:microsoft:windows_server_2016:1909:*:*:*:*:*:*:*cpe:2.3:o:microsoft:windows_server_2016:2004:*:*:*:*:*:*:*cpe:2.3:o:microsoft:windows_server_2019:-:*:*:*:*:*:*:*cpe:2.3:a:samba:samba:*:*:*:*:*:*:*:*≥ 4.1.0 < 4.13.13cpe:2.3:a:samba:samba:*:*:*:*:*:*:*:*≥ 4.14.0 < 4.14.9cpe:2.3:a:samba:samba:*:*:*:*:*:*:*:*≥ 4.15.0 < 4.15.1
Affected products
Sources
| Source | Licence |
|---|---|
| CVE List (CVEProject cvelistV5) | CVE Program Terms of Use |
| EPSS (FIRST.org) | FIRST — attribution requested |
| ENISA EUVD | ENISA — reproduction authorised, source acknowledged |
| CERT-FR (ANSSI) | Licence Ouverte / Etalab 2.0 |
| NVD (NIST) via fkie-cad/nvd-json-data-feeds | Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD |