CVE-2026-64813 is a critical security flaw affecting JetBrains IntelliJ IDEA versions released before 2026.2. The vulnerability arises from insufficient access controls in Remote Development sessions, permitting unauthorized actors to modify application settings without proper authentication. This could lead to configuration tampering, data exfiltration, or execution of arbitrary code in affected environments. The CVSS score of 10.0 reflects the high severity due to the ease of exploitation and potential for remote code execution. Users of IntelliJ IDEA and JetBrains Remote Development platforms running unpatched versions are at risk. Attackers could exploit this flaw to disrupt workflows, compromise sensitive project configurations, or establish persistent access. Immediate action is required: upgrade to version 2026.2 or later to mitigate the risk. Organizations should prioritize patching all instances of affected software and monitor for suspicious activity in remote development environments. This vulnerability underscores the importance of maintaining up-to-date software in collaborative development ecosystems.