A vulnerability in the lighttpd module of Cisco IOS XR could allow an unauthenticated, remote attacker to cause a reload of the affected lighttpd process. The vulnerability is due to a race condition while handling TCP sessions to the lighttpd module on the affected Cisco IOS XR device. An attacker could exploit this vulnerability by sending a number of TCP sessions to be established with the lighttpd server on the affected device. An exploit could allow the attacker to cause a reload of the lighttpd process. Cisco has confirmed the vulnerability in a security notice and released software updates. To exploit this vulnerability, an attacker may need access to trusted, internal networks behind a firewall to send numerous TCP sessions to the targeted device. This access requirement may reduce the likelihood of a successful exploit. Cisco indicates through the CVSS score that functional exploit code exists; however, the code is not known to be publicly available.
The Cisco Product Security Incident Response Team (PSIRT) is not aware of any public announcements or malicious use of the vulnerability that is described in this advisory.
To learn about Cisco security vulnerability disclosure policies and publications, see the Security Vulnerability Policy. This document also contains instructions for obtaining fixed software and receiving security vulnerability information from Cisco.
| Version | Description | Section | Status | Date |
| 1.0 | Initial Release | NA | Final | 2014-Nov-25 |
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