This post was authored by Earl Carter & Yves Younan.
Talos is constantly researching the ways in which threat actors take advantage of security weaknesses to exploit systems. Use-after-free vulnerabilities have become an important class of security problems due to the existence of mitigations that protect against other types of vulnerabilities, such as buffer overflows. Today, Talos is releasing FreeSentry, a mitigation for use-after-free vulnerabilities.
FreeSentry works as a plugin for LLVM with an associated runtime library that tracks pointers when they are set to objects and invalidates them when the memory associated with that object is freed. Our initial approach was published at the 2015 Network and Distributed System Security (NDSS) Symposium in February. The paper can be downloaded here. At CanSecWest 2015, Yves Younan of Talos presented an enhanced version of FreeSentry which included further developments, such as porting the original mitigation from C Intermediate Language (CIL) to LLVM. The CanSecWest slides are available here. Note that the LLVM performance numbers in the CanSecWest presentation were preliminary numbers, and have been updated for this post.
Read More »
Tags: mitigations, Talos, Threat Research, Use-After-Free
Cisco Live, May 18-24, 2014, is quickly approaching and registration is open. This is the 25th anniversary of Cisco Live and we return to the Bay Area at San Francisco’s Moscone Center. Educational sessions are organized into technology tracks to make it easy to find the topics that most interest you. With network and data security being top of mind, I’d like to highlight the Security technology track’s exciting content lineup. Read More »
Tags: ASA, byod, cisco live, Cisco Live US, Cisco Live! 2014, Cloud Computing, cybersecurity, data security, firewall, IoT, malware, mitigations, network security, Network Threat Defense, psirt, security, security training, training, vpn
On April 10, 2013, a collective of politically motivated hacktivists announced a round of planned attacks called #OPUSA. These attacks, slated to begin May 7, 2013, are to be launched against U.S.-based targets. #OPUSA is a follow-up to #OPISRAEL, which were a series of attacks carried out on April 7 against Israeli-based targets. Our goal here is to summarize and inform readers of resources, recommendations, network mitigations, and best practices that are available to prevent, mitigate, respond to, or dilute the effectiveness of these attacks. This blog was a collaborative effort between myself, Kevin Timm, Joseph Karpenko, Panos Kampanakis, and the Cisco TRAC team.
If the attackers follow the same patterns as previously witnessed during the #OPISRAEL attacks, then targets can expect a mixture of attacks. Major components of previous attacks consisted of denial of service attacks and web application exploits, ranging from advanced ad-hoc attempts to simple website defacements. In the past, attackers used such tools as LOIC, HOIC, and Slowloris.
Publicly announced attacks of this nature can have highly volatile credibility. In some cases, the announcements exist only for the purpose of gaining notoriety. In other cases, they are enhanced by increased publicity. Given the lack of specific details about participation or capabilities, the exact severity of the attack can’t be known until it (possibly) happens. Read More »
Tags: advisories, ASA, botnet, botnets, Cisco Security, Cloud Computing, cloud security, data center security, DDoS, exploits, firewall, incident response, IPS, IPS signatures, malware, mitigations, security, targeted attacks, TRAC, vulnerability
Cross-Site Request Forgery (CSRF) attacks: there are already enough articles out there that can explain what a CSRF attack is and provide potential examples. There are also plenty of security alerts that have been released by various vendors whose products are affected by CSRF-related vulnerabilities.
CSRF attacks usually target web applications and attempt to make unwanted changes on server data or extract sensitive information from a web application. Attackers do this by luring an authenticated user into making a specially crafted web request. It’s important, regardless of role, for everyone to have a basic understanding of CSRF attacks and the available options to protect against them.
For more information about basic CSRF concepts and potential mitigations, see our new Applied Mitigation Bulletin Understanding Cross-Site Request Forgery Threat Vectors. Although this document does not attempt to provide all the technical details associated with CSRF, it does aim to summarize the CSRF technique and provide methods that can be potentially used by developers, network administrators and users to protect against CSRF attacks.
For all things related to Security don’t forget to visit the Cisco Security Intelligence Operations (SIO) Portal—the primary outlet for Cisco’s security intelligence and the public home to all of our security-related content. Just go to cisco.com/security.
Tags: Applied Mitigation Bulletins, Cisco Security, cisco sio, cross-site request forgery, CSRF, CSRF attacks, mitigations
We are often asked by customers about how they can prevent traffic from a certain country (let’s say country X) from entering their network. The motivations for doing this could vary. Sometimes a company does not do business with all countries in the world; therefore, the company doesn’t need to be accessible from all countries. Other times it is an issue of trust and security, where an administrator may not want to allow country X to enter their infrastructure. Finally, there are cases where country X has often been incriminated with malicious activity, so an administrator may want to block country X when there is no need for the organization to interact with this country. In this document I present a methodology on how to write a tool that provides the configuration lines to block country X, using your IOS router or ASA/ASASM firewall.
Read More »
Tags: ASA, filters, firewall, internet traffic, IOS, mitigations, security