---------------------------------------------------------------------- Secunia is proud to announce the availability of the Secunia Software Inspector. The Secunia Software Inspector is a free service that detects insecure versions of software that you may have installed in your system. When insecure versions are detected, the Secunia Software Inspector also provides thorough guidelines for updating the software to the latest secure version from the vendor. Try it out online: http://secunia.com/software_inspector/ ---------------------------------------------------------------------- TITLE: Cisco IOS VTP Denial of Service Vulnerability SECUNIA ADVISORY ID: SA23892 VERIFY ADVISORY: http://secunia.com/advisories/23892/ CRITICAL: Less critical IMPACT: DoS WHERE: >From local network OPERATING SYSTEM: Cisco IOS 12.x http://secunia.com/product/182/ Cisco IOS R12.x http://secunia.com/product/50/ DESCRIPTION: David Barroso Berrueta and Alfredo Andres Omella have reported a vulnerability in Cisco IOS, which can be exploited by malicious people to cause a DoS (Denial of Service). The vulnerability is caused due to an unspecified error when handling certain malformed VLAN Trunking Protocol (VTP) packets. This can be exploited to cause a device to reload by sending a specially crafted VTP packet. Successful exploitation requires knowledge of the VTP domain name and the port that is configured for trunking. The vulnerability is reported in the following devices: * Cisco 2900XL Series Switches * Cisco 2950 Series Switches * Cisco 2955 Series Switches * Cisco 3500XL Series Switches * Cisco 3550 Series Switches * Cisco 3570 Series Switches SOLUTION: The vendor recommends allowing only trusted devices to connect to ports configured for ISL or 802.1q trunking. PROVIDED AND/OR DISCOVERED BY: Alfredo Andres Omella and David Barroso Berrueta, S21SEC ORIGINAL ADVISORY: Cisco Advisory: http://www.cisco.com/en/US/products/products_security_response09186a00807d1a81.html 21SEC Advisory: http://www.s21sec.com/es/avisos/s21sec-034-en.txt ---------------------------------------------------------------------- About: This Advisory was delivered by Secunia as a free service to help everybody keeping their systems up to date against the latest vulnerabilities. Subscribe: http://secunia.com/secunia_security_advisories/ Definitions: (Criticality, Where etc.) http://secunia.com/about_secunia_advisories/ Please Note: Secunia recommends that you verify all advisories you receive by clicking the link. Secunia NEVER sends attached files with advisories. Secunia does not advise people to install third party patches, only use those supplied by the vendor. ---------------------------------------------------------------------- Unsubscribe: Secunia Security Advisories http://secunia.com/sec_adv_unsubscribe/?email=packet%40packetstormsecurity.org ----------------------------------------------------------------------