CVE-2014-3308

Vulnerability

Cisco IOS XR Software on Trident line cards in ASR 9000 Series Aggregation Services Routers lacks a static punt policer. This vulnerability, identified by Cisco bug ID CSCun83985, allows an unauthenticated attacker to cause excessive CPU consumption by sending a high volume of crafted packets to the affected device. Affected versions include Cisco IOS XR releases running on Trident line cards.

Exploitation

An attacker can exploit this vulnerability from a remote network without authentication by sending a large number of crafted packets to the device. No special privileges or user interaction is required. The attack targets the punt path, where excessive traffic overwhelms the CPU due to the missing static policer.

Impact

Successful exploitation leads to CPU exhaustion on the affected line card, resulting in a denial of service (DoS) condition. The device may become unresponsive or drop valid traffic. The impact is limited to CPU consumption; no data disclosure or privilege escalation is reported.

Mitigation

Cisco has not released a software update for this vulnerability at the time of disclosure. Mitigations include implementing access control lists (ACLs) to limit traffic to the punt path or deploying rate limiters. Users should monitor Cisco Security Advisories for future patches. [1]