Cisco Systems released software security updates Wednesday to address denial-of-service and arbitrary command execution vulnerabilities in several products, including a known flaw in the Apache Struts development framework used by some of them.
The company released new versions of Cisco IOS XR Software to fix an issue with handling fragmented packets that can be exploited to trigger a denial-of-service condition on various Cisco CRS Route Processor cards. The affected cards and the patched software versions available for them are listed in a Cisco advisory.
The company also released security updates for Cisco Identity Services Engine (ISE), a security policy management platform for wired, wireless, and VPN connections. The updates fix a vulnerability that could be exploited by authenticated remote attackers to execute arbitrary commands on the underlying operating system and a separate vulnerability that could allow attackers to bypass authentication and download the product's configuration or other sensitive information, including administrative credentials.
Cisco also released updates that fix a known Apache Struts vulnerability in several of its products, including ISE. Apache Struts is a popular open-source framework for developing Java-based Web applications.
The vulnerability, identified as CVE-2013-2251, is located in Struts' DefaultActionMapper component and was patched by Apache in Struts version 188.8.131.52 which was released in July.
The new Cisco updates integrate that patch into the Struts version used by Cisco Business Edition 3000, Cisco Identity Services Engine, Cisco Media Experience Engine (MXE) 3500 Series and Cisco Unified SIP Proxy.
"The impact of this vulnerability on Cisco products varies depending on the affected product," Cisco said in an advisory. "Successful exploitation on Cisco ISE, Cisco Unified SIP Proxy, and Cisco Business Edition 3000 could result in an arbitrary command executed on the affected system."
No authentication is needed to execute the attack on Cisco ISE and Cisco Unified SIP Proxy, but the flaw's successful exploitation on Cisco Business Edition 3000 requires the attacker to have valid credentials or trick a user with valid credentials into executing a malicious URL, the company said.
"Successful exploitation on the Cisco MXE 3500 Series could allow the attacker to redirect the user to a different and possibly malicious website, however arbitrary command execution is not possible on this product," Cisco said.
Security researchers from Trend Micro reported in August that Chinese hackers are attacking servers running Apache Struts applications by using an automated tool that exploits several Apache Struts remote command execution vulnerabilities, including CVE-2013-2251.
The existence of an attack tool in the cybercriminal underground for exploiting Struts vulnerabilities increases the risk for organizations using the affected Cisco products.
In addition, since patching CVE-2013-2251 the Apache Struts developers have further hardened the DefaultActionMapper component in more recent releases.
Struts version 184.108.40.206, which was released in September, made some changes to the DefaultActionMapper "action:" prefix that's used to attach navigational information to buttons within forms in order to mitigate an issue that could be exploited to circumvent security constraints. The issue has been assigned the CVE-2013-4310 identifier.
Struts 220.127.116.11, released on Oct. 17, turned off support for the "action:" prefix by default and added two new settings called "struts.mapper.action.prefix.enabled" and "struts.mapper.action.prefix.crossNamespaces" that can be used to better control the behavior of DefaultActionMapper.
The Struts developers said that upgrading to Struts 18.104.22.168 is strongly recommended, but held back on releasing more details about CVE-2013-4310 until the patch is widely adopted.
It's not clear when or if Cisco will patch CVE-2013-4310 in its products, giving that the fix appears to involve disabling support for the "action:" prefix. If the Struts applications in those products use the "action:" prefix the company might need to rework some of their code.