CVE-2026-10535 is a stack-based buffer overflow vulnerability (CWE-121) in the setgid helper db2flacc component of IBM Db2 versions 11.5.0 and 12.1.0. This vulnerability could allow an attacker to execute arbitrary code or cause a denial of service by overflowing a buffer on the stack. The vulnerability has a CVSS v3.1 base score of 8.4, indicating high severity with attack vector local, low attack complexity, no privileges required, no user interaction, and impacts to confidentiality, integrity, and availability. No vendor advisory or patch information is currently available.

Successful exploitation of this vulnerability could lead to full compromise of the affected IBM Db2 system, including unauthorized disclosure, modification, or destruction of data, and potential denial of service. The vulnerability affects critical components with high impact on confidentiality, integrity, and availability.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is released, restrict local access to the affected systems and monitor for suspicious activity related to the db2flacc helper. Avoid running untrusted code or commands with elevated privileges on affected versions.