Cisco IOS 12.0 to 12.4 might allow remote attackers to execute arbitrary code via a heap-based buffer overflow in system timers. NOTE: this issue does not correspond to a specific vulnerability, rather a general weakness that only increases the feasibility of exploitation of any vulnerabilities that might exist. Such design-level weaknesses normally are not included in CVE, so perhaps this issue should be REJECTed.
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A4914
http://www.vupen.com/english/advisories/2005/2282
http://www.securityfocus.com/bid/15275
http://www.kb.cert.org/vuls/id/562945
http://www.cisco.com/warp/public/707/cisco-sa-20051102-timers.shtml