Cisco has released eight security updates for the IOS (Internetwork Operating System) software used to power its routers.
The patches were released Wednesday, the day Cisco had previously scheduled for its twice-yearly IOS updates. None of the bugs had been publicly disclosed ahead of Wednesday's updates, but some of them were reported to Cisco by outside sources.
[ Learn how to secure your systems with Roger Grimes' Security Adviser blog and newsletter, both from InfoWorld. ]
The eight updates fix 11 security vulnerabilities, according to Jean Reese, senior manager with Cisco's Product Security Incident Response Team.
Most of the bugs could be exploited by attackers to crash or somehow disrupt service to a router, typically if a specific, vulnerable service is enabled, Cisco said.
For example, Cisco has fixed two bugs in its SSLVPN (Secure Sockets Layer Virtual Private Network) software that could be used to crash the device. Attackers could exploit one of these bugs by sending a specially crafted HTTPS packet to the router. The bug does not affect users of the company's ASA 5500 appliance or of Cisco IOS XR or XE software, however.
SSLVPN lets users outside of the corporate firewall access their company's network using a Web browser, instead of installing special VPN software on their PC.
Another serious bug affects those who have enabled the Secure Copy Protocol (SCP), used to allow file transfers over the network. Because of this bug, an authenticated user on the device could "transfer files to and from a Cisco IOS device that is configured to be an SCP server, regardless of what users are authorized to do," Cisco said in its advisory. This could allow a user to mess with the router's configuration files or sneak a peek at passwords, Cisco said. This bug was reported to Cisco by Kevin Graham, the company said.
For the bug to be exploited, the Cisco user would need to have a command line interface (CLI) on the router. "The SCP bug is pretty bad if you have read-only CLI users," said Felix Lindner, a noted Cisco expert who is head of Recurity Labs, in an e-mail interview. "If you are a read-only CLI user and this bug allows you to write the configuration or, even worse, a new backdoored IOS image. That's evil."
According to sources familiar with the matter, Cisco and other vendors have been working on patching a major TCP/IP bug in its routers that could be exploited in what's called a Sockstress attack. This flaw, which has not been disclosed publicly, could be used to take down a router using a very low-bandwidth denial of service attack.
Reese wouldn't comment on whether this bug was patched in Wednesday's updates. The company did not credit the two researchers who first discussed the Sockstress attack in any of its updates, a sign that the issue may not have been patched.
More details on the updates can be found on Cisco's Web site.
Cisco's next set of IOS patches is due Sept. 23.
This story was updated on March 25, 2009.
Get the independent advice and expertise you need to support a virtual workforce.
The increase in Linux popularity has increased the frequency and sophistication of malware attacks. Read this 2 page white paper now to learn how you can protect your Linux environment with real-time protection that is certified by all major Linux vendors.
Download now »Ensuring acceptable application delivery will become even more difficult over the next few years. As a result, IT organizations need to ensure that the approach that they take to resolving the current application delivery challenges can scale to support the emerging challenges. This handbook elaborates on the key tasks associated with planning, optimization, management and control and provides decision criteria to help IT organizations choose appropriate solutions.
Download now »A common misconception is that mid-range storage requirements are dramatically different than that of a larger enterprise. Mid-range storage users may require less capacity, but they have similar functionality and management requirements. This ESG paper examines mid-range storage needs and reviews a new solution that adjusts size while retaining value, performance and functionality.
Download now »
Sign up to receive Security Resource Alerts
This white paper provides guidance on how to develop a strategic approach to managing and monitoring logs, a key function required for compliance with many regulatory mandates and a critical defense against security threats.
Download now! »Learn about the processes and technologies that support security information management (SIM) operations, as well as the business case for SIM. The series examines different options for implementing SIM and gives you evaluation criteria for selecting the best option for your organization.
Download now! »Learn the strategies, actions, and capabilities that Best-in-Class organizations employ and technologies they choose to obtain superior performance against various security performance metrics. This report provides guidelines for identifying which security solutions to consume as a MSS and defines best practices for choosing and managing MSSPs.
Download now! »