CVE-2025-20177

CVE-2025-20177 is a high-severity vulnerability in Cisco IOS XR Software that allows an authenticated, local attacker with root-system privileges to bypass image signature verification during the boot process. This enables the loading of unverified software, due to incomplete validation of boot files. A successful exploit could allow the attacker to control the boot configuration, bypass the requirement for Cisco-signed images, or alter the system's security properties. While there is no known active exploitation or public exploit code, the vulnerability has garnered some community discussion and media coverage, leading Cisco to raise its Security Impact Rating to High.