CVE-2020-17049 : A security feature bypass vulnerability exists in the way Key Distribution Center (KDC) determines if a service ticke

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.

Published 2020-11-11 07:15:17

Updated 2023-12-31 19:15:23

Source Microsoft Corporation

View at NVD, CVE.org

Threat overview for CVE-2020-17049

Top countries where our scanners detected CVE-2020-17049

Top open port discovered on systems with this issue 445

IPs affected by CVE-2020-17049 121,934

Threat actors abusing to this issue? Yes

Find out if you^* are affected by CVE-2020-17049!

^*Directly or indirectly through your vendors, service providers and 3rd parties. Powered by attack surface intelligence from SecurityScorecard.

Exploit prediction scoring system (EPSS) score for CVE-2020-17049

Probability of exploitation activity in the next 30 days: 2.74%

Percentile, the proportion of vulnerabilities that are scored at or less: ~ 89 % EPSS Score History EPSS FAQ

CVSS scores for CVE-2020-17049

Base Score	Base Severity	CVSS Vector	Exploitability Score	Impact Score	Score Source
9.0	HIGH	AV:N/AC:L/Au:S/C:C/I:C/A:C	8.0	10.0	NIST
Access Vector: Network Access Complexity: Low Authentication: Single Confidentiality Impact: Complete Integrity Impact: Complete Availability Impact: Complete
7.2	HIGH	CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H	1.2	5.9	NIST
Attack Vector: Network Attack Complexity: Low Privileges Required: High User Interaction: None Scope: Unchanged Confidentiality: High Integrity: High Availability: High
6.6	MEDIUM	CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H	0.7	5.9	Microsoft Corporation
Attack Vector: Network Attack Complexity: High Privileges Required: High User Interaction: None Scope: Unchanged Confidentiality: High Integrity: High Availability: High

CWE ids for CVE-2020-17049

CWE-863 Incorrect Authorization

The product performs an authorization check when an actor attempts to access a resource or perform an action, but it does not correctly perform the check. This allows attackers to bypass intended access restrictions.

Assigned by: nvd@nist.gov (Primary)

References for CVE-2020-17049

https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-17049

CVE-2020-17049 - Security Update Guide - Microsoft - Kerberos Security Feature Bypass Vulnerability
Patch;Vendor Advisory
http://www.openwall.com/lists/oss-security/2021/11/10/3

oss-security - Fwd: Samba 4.15.2, 4.14.10, 4.13.14 Security Releases are available for Download
Mailing List;Third Party Advisory
https://security.gentoo.org/glsa/202309-06

Samba: Multiple Vulnerabilities (GLSA 202309-06) — Gentoo security

CVEs referencing this url

Products affected by CVE-2020-17049