EUVD-2026-56373
GHSA-rh92-837f-hgq8
Severity by source
AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Local vector and low-privilege requirement are consistent with the described authenticated local exploitation; full C/I/A impact reflects attainment of SYSTEM-level privileges with no scope change.
Primary rating from Vendor (microsoft).
CVSS VectorVendor: microsoft
Lifecycle Timeline
3DescriptionCVE.org
Heap-based buffer overflow in Windows Kerberos allows an authorized attacker to elevate privileges locally.
AnalysisAI
Heap-based buffer overflow in the Windows Kerberos authentication subsystem enables a locally authenticated attacker to elevate privileges to SYSTEM-level access across a broad range of Windows client and server releases. The CVSS 3.1 score of 7.8 (AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H) reflects full confidentiality, integrity, and availability impact upon successful exploitation with low attack complexity once local access is established. Microsoft has released patches per MSRC advisory CVE-2026-62754; no public exploit code has been identified and the vulnerability has not appeared in the CISA KEV catalog at time of analysis.
Technical ContextAI
CWE-122 (Heap-based Buffer Overflow) describes a write operation that exceeds the bounds of a heap-allocated memory region, which can corrupt adjacent heap metadata, overwrite function pointers, or enable arbitrary code execution. The affected component is the Windows Kerberos implementation, which provides RFC 4120 Kerberos v5 ticket-based authentication and is the default protocol for Active Directory-joined systems. The overflow likely occurs during parsing of Kerberos authentication structures - such as ticket data, cryptographic payloads, or AS-REQ/TGS-REQ message fields - where user-controlled length values are not adequately validated before buffer copy operations. Exploitation on Windows heap internals may leverage segment heap metadata corruption or lookaside list manipulation to redirect code execution. Affected products span a wide CPE surface: Windows client editions from 10 Version 1607 through 11 Version 26H1, and Windows Server editions from 2012 through 2025, all documented under EUVD-2026-56373.
RemediationAI
Apply the Microsoft security updates documented in the MSRC advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-62754. The minimum patched build per platform, as confirmed by EUVD-2026-56373, is: Windows Server 2012 to 6.2.9200.26279, Windows Server 2012 R2 to 6.3.9600.23337, Windows Server 2016 and Windows 10 Version 1607 to 10.0.14393.9418, Windows Server 2019 and Windows 10 Version 1809 to 10.0.17763.9115, Windows 10 Version 21H2 to 10.0.19044.7663, Windows 10 Version 22H2 to 10.0.19045.7663, Windows Server 2022 to 10.0.20348.5499, Windows Server 2025 to 10.0.26100.33296, Windows 11 Version 24H2 to 10.0.26100.9168, Windows 11 Version 25H2 to 10.0.26200.9168, and Windows 11 Version 26H1 to 10.0.28000.2704. For systems pending patch deployment, reduce exposure by enforcing the principle of least privilege and restricting interactive and remote (RDP) logon rights to only operationally required accounts via Group Policy - note this does not eliminate risk where multi-user access is legitimate. Additionally, enable advanced audit logging for Kerberos authentication events (Event IDs 4768, 4769, 4771) to detect anomalous ticket request patterns that may indicate exploitation attempts, though this is a detection rather than prevention control.
More in Windows 10 1607
View allWindows MSHTML component contains a remote code execution vulnerability that allows attackers to craft malicious ActiveX
<p>A remote code execution vulnerability exists when the Windows Print Spooler service improperly performs privileged fi
Windows MSDT (Microsoft Support Diagnostic Tool) allows remote code execution when called via the ms-msdt URL protocol f
The SMBv1 server in Microsoft Windows Vista SP2; Windows Server 2008 SP2 and R2 SP1; Windows 7 SP1; Windows 8.1; Windows
The Windows VBScript engine contains a remote code execution vulnerability in object handling that allows full system co
Windows Print Spooler Remote Code Execution Vulnerability. Rated high severity (CVSS 7.8), this vulnerability is no auth
The Win32k kernel-mode driver in Windows Vista through Windows Server 2016 allows local privilege escalation, exploited
Windows Search Remote Code Execution Vulnerability. Rated high severity (CVSS 7.5), this vulnerability is remotely explo
Denial of service against HTTP/2 server implementations allows remote unauthenticated attackers to exhaust server resour
Windows Kernel contains a TOCTOU race condition vulnerability allowing local privilege escalation, exploited by the OilR
An elevation of privilege vulnerability exists in Windows when the Win32k component fails to properly handle objects in
An elevation of privilege vulnerability exists in Windows when the Win32k component fails to properly handle objects in
Same weakness CWE-122 – Heap-based Buffer Overflow
View allSame technique Buffer Overflow
View allShare
External POC / Exploit Code
Leaving vuln.today