Cisco has addressed several critical vulnerabilities in IOS XR software, including issues that could lead to DoS attacks and bypass of security verification processes. These updates enhance the security and stability of affected devices against potential exploitation. #IOSXR #CVE202520340
Keypoints
- Cisco issued fixes for multiple vulnerabilities in IOS XR software in September 2025.
- The most severe vulnerability, CVE-2025-20340, allows attackers to trigger broadcast storms and cause device DoS by overwhelming ARP processing.
- A high-severity flaw, CVE-2025-20248, permits bypassing image signature verification during the installation process.
- Attackers need root privileges to exploit the signature bypass vulnerability and can insert unsigned files into ISO images.
- A medium-severity flaw (CVE-2025-20159) enables remote attackers to bypass ACLs for SSH, NetConf, and gRPC on affected devices.