In a coordinated response with the developer, the GitHub Security Lab is disclosing CVE-2023-43641, a memory corruption vulnerability in libcue, a library used for parsing cue sheets—a metadata format for describing the layout of the tracks on CDs.
“libcue provides an API for parsing and extracting data from CUE sheets. Versions 2.2.1 and prior are vulnerable to out-of-bounds array access,” according to NIST.
“ A user of the GNOME desktop environment can be exploited by downloading a cue sheet from a malicious webpage. Because the file is saved to `~/Downloads`, it is then automatically scanned by tracker-miners. And because it has a .cue filename extension, tracker-miners use libcue to parse the file. The file exploits the vulnerability in libcue to gain code execution.”
Takeaway: Anytime you have a vulnerability that can allow for remote code execution (RCE), it's potentially a pretty serious for those organizations affected.
Luckily in this case it seems there would need to be actions taken on the user side in order to fall victim to an exploit, as opposed to vulnerabilities being actively exploited by ransomware gangs like the MoveIT and GoAnywhere FTPs that do not require user actions to initiate the exploit.
Nonetheless, if a patch is available and it can be swiftly implemented without breaking anything in production, it should be applied immediately.
Even if an organization has ample resources to stand up a very mature security program, it may take the exploitation of just one unpatched vulnerability to bring them to their knees, as we have seen repeatedly in the mass exploitation of the MOVEit and GoAnywhere file transfer software in 2023.
Organizations cannot simply focus on deploying preventative technologies and data backups and expect that to be enough. Threat actors have proven time and again that they can easily bypass or blind Endpoint Protection tools like AV/NGAV/EDR/XDR.
Organizations have to prepare for the worst-case scenarios in which a ransomware attack is successful, and data has been exfiltrated for added pressure to pay. Organizations require both a robust prevention and an agile resilience strategy to defend against this wave of ransomware attacks.
This approach includes endpoint protection solutions, patch management, data backups, access controls, and employee awareness training. Most important is to test these precautions through regular procedure and resilience testing.
Resilience is the key here, and tabletop exercises will help organizations better understand where the gaps in their business continuity plans exist.
Our advice to organizations is to regularly stress test their defense as well as go through all the motions for remediation and recovery to assure all stakeholders are ready to jump into action when needed - time is critical.
Halcyon.ai is the industry’s first dedicated, adaptive security platform that combines multiple advanced proprietary prevention engines along with AI models focused specifically on stopping ransomware – talk to a Halcyon expert today to find out more. Halcyon also publishes a quarterly RaaS and extortion group reference guide, Power Rankings: Ransomware Malicious Quartile (PDF).