A vulnerability in Cisco ISE could allow an authenticated, remote attacker to obtain write access on the underlying operating system of an affected device. This vulnerability is due to insufficient validation of user-supplied input. An attacker could exploit this vulnerability by sending a crafted HTTP request to an affected device. A successful exploit could allow the attacker to obtain write access to the underlying operating system. To exploit this vulnerability, the attacker must have valid administrative credentials. Note: For CVE-2026-20282, Cisco has assigned a Security Impact Rating (SIR) of High rather than Medium as the score indicates. The reason is that it is easy to get to root from the achieved privilege level.