cbcvebase.
CVE-2024-43639
published 2024-11-12

CVE-2024-43639: Windows KDC Proxy Remote Code Execution Vulnerability

PriorityP268critical9.8CVSS 3.1
AVNACLPRNUINSUCHIHAH
EPSS
8.75%
94.5th percentile
Windows KDC Proxy Remote Code Execution Vulnerability

Affected

19 ranges
VendorProductVersion rangeFixed in
microsoftwindows_server_2012
microsoftwindows_server_2012>= 6.2.9200.0 < 6.2.9200.251656.2.9200.25165
microsoftwindows_server_2012_r2>= 6.3.9600.0 < 6.3.9600.222676.3.9600.22267
microsoftwindows_server_2016< 10.0.14393.751510.0.14393.7515
microsoftwindows_server_2016>= 10.0.14393.0 < 10.0.14393.751510.0.14393.7515
microsoftwindows_server_2019< 10.0.17763.653210.0.17763.6532
microsoftwindows_server_2019>= 10.0.17763.0 < 10.0.17763.653210.0.17763.6532
microsoftwindows_server_2022< 10.0.20348.284910.0.20348.2849
microsoftwindows_server_2022>= 10.0.20348.0 < 10.0.20348.284910.0.20348.2849
microsoftwindows_server_2022_23h2< 10.0.25398.125110.0.25398.1251
microsoftwindows_server_2025< 10.0.26100.231410.0.26100.2314
microsoftwindows_server_2025>= 10.0.26100.0 < 10.0.26100.231410.0.26100.2314
msrcwindows_server_2012
msrcwindows_server_2012_r2
msrcwindows_server_2016
msrcwindows_server_2019
msrcwindows_server_2022
msrcwindows_server_2022_23h2_edition
msrcwindows_server_2025

Detection & IOCsextracted from sources · hover to see the quote

  • Vulnerability only exists on servers running the KDC Proxy Server service (KPSSVC). Detection should focus on identifying hosts with KPSSVC running and exposed.
  • Only Windows Servers configured as MS-KKDCP (Kerberos Key Distribution Center Proxy Protocol) servers are vulnerable — domain controllers are NOT affected. Scope detection/hunting to KKDCP proxy servers specifically.
  • Attack vector is unauthenticated and remote, delivered via a specially crafted application exploiting a cryptographic protocol flaw in Windows Kerberos. Monitor KPSSVC for anomalous or malformed inbound Kerberos proxy requests from unauthenticated sources.
  • KPSSVC will NOT start on-demand; if it is running, the system is actively vulnerable. Audit service state of KPSSVC (KDC Proxy Server service) across the environment as a detection/exposure check.
  • ·Exploitation requires KPSSVC to already be running and configured; systems without KPSSVC enabled are not exploitable, limiting the attack surface to intentionally deployed KDC Proxy servers.
  • ·Domain controllers running standard KDC are NOT affected — only dedicated KKDCP proxy servers are in scope, which may reduce false-positive risk when scoping detection rules.

CVSS provenance

nvdv3.19.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
vendor_msrc9.8CRITICAL
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