CVE-2026-69829 – Windows Shell Remote Code Execution Vulnerability

CVE-2026-69829 is a Critical heap-based buffer overflow vulnerability in Windows Shell. An unauthorized attacker can exploit the flaw over a network by calling arbitrary endpoints, potentially gaining remote code execution. Successful exploitation could severely affect the confidentiality, integrity, and availability of an affected Windows system.

CVSS SCORE: 9.8.

SEVERITY: Critical.

THREAT: The vulnerability has a network attack vector, low attack complexity, and requires neither privileges nor user interaction. Successful exploitation can allow an unauthorized attacker to execute code remotely, with high potential impact to confidentiality, integrity, and availability.

EXPLOITS: This vulnerability is not publicly disclosed and is not reported as exploited. Exploit code maturity is Unproven, and the exploitation assessment is Exploitation Unlikely. No confirmed public exploit, zero-day exploitation, or proof-of-concept exploit code is identified.

TECHNICAL SUMMARY: CVE-2026-69829 is caused by a heap-based buffer overflow (CWE-122) in Windows Shell. An in-network attacker can target arbitrary endpoints over the network to trigger the vulnerability. The attack has low complexity and does not require existing privileges or user interaction. Successful exploitation can result in remote code execution, with high confidentiality, integrity, and availability impacts. An official fix is identified.

EXPLOITABILITY: Affected products include Windows 10 versions 1607, 1809, 21H2, and 22H2; Windows 11 versions 23H2, 24H2, 25H2, and 26H1; and Windows Server 2012, 2012 R2, 2016, 2019, 2022, and 2025, including the listed Server Core installations and supported architectures. Exploitation can occur over a network through an in-network attacker calling arbitrary endpoints.

BUSINESS IMPACT: Successful exploitation could give an unauthorized attacker remote code execution on affected Windows systems. Because confidentiality, integrity, and availability impacts are all rated High, compromise could expose sensitive information, permit unauthorized system changes, and disrupt critical Windows services or business operations.

WORKAROUND: No mitigation or workaround is identified. An official fix is available, and affected systems require a restart according to the affected-software entries.

URGENCY: This vulnerability is rated Critical with a CVSS base score of 9.8 and can enable remote code execution with low attack complexity, no privileges, and no user interaction. Although exploitation is assessed as unlikely and no exploitation is reported, the potential impact makes timely deployment of the official fix important.