The new Codefinger ransomware poses a high risk to data.
Update, January 14, 2025: This story, originally published on January 13, now includes analysis from security experts, as the nature of Amazon’s threat is fully revealed, on how new plans to make ransomware payments illegal could affect to the victims of such cybercrimes. , plus further mitigation tips.
Ransomware is a cybersecurity threat that just won’t go away. Whether it’s from groups like those behind the ongoing Play attacks, or kingpins like LockBit coming back from the dead, the consequences of being the victim of an attack are revealed in reports that expose the extent of ransomware through 2024. A new threat The ransomware, known as Codefinger, targeting users of Amazon Web Services S3 buckets has now been confirmed. Here’s what you need to know.
Ongoing Codefinger Ransomware attacks target Amazon Cloud users
A new ransomware campaign targeting Amazon Web Services users by a threat actor known as Codefinger has been confirmed in a Jan. 13 threat intelligence report from the Halcyon threat intelligence and research team. The Codefinger attack exploits AWS server-side encryption with client-supplied keys, thankfully usually shortened to SSE-C, in order to encrypt data and then demand payment for the AES-256 symmetric keys required to decrypt it with success. “This ransomware campaign is particularly dangerous due to the design of SSE-C,” Halcyon researchers warned, “integrating directly with AWS’ secure encryption infrastructure and encrypting data, recovery is impossible without the attacker’s key.”
Halcyon has gone so far as to suggest that Codefinger represents a significant evolution in ransomware capabilities, adding that: “If this spreads quickly, it could pose a systemic threat to organizations using AWS S3 to store critical data.” I’m not sure I can fully agree that not being able to decrypt data without paying for a key is evolutionary, it’s the basis on which all ransomware works, after all, but using SSE-C is certainly a new approach. “Unlike traditional ransomware that encrypts files locally or in transit, this attack integrates directly with AWS’s secure encryption infrastructure,” the researchers said, “once encrypted, recovery is impossible without the attacker’s key.”
All that said, the attack campaign does not exploit any AWS vulnerabilities, instead relying on the age-old tactic of obtaining an AWS customer’s account credentials by hook or by crook.
“This is a great example of where password reuse or sticking with easy-to-guess passwords, along with no two-factor authentication, will backfire on the admin,” said Darren James, a senior manager product at Specops Software. If people had ensured that they used different passwords for all systems, as well as enabling strong, phishing-resistant 2FA wherever possible, James said, “this latest ransomware attack could have been avoid. On the other hand, at least SSE-C is a strong encryption method, but it’s not good to see it used against the good guys rather than for them.”
Flow of Kodofinger Ransomware Attack on Amazon Cloud
The Halcyon Report reported that the attack flow used by Codefinger is as follows:
- Identify vulnerable AWS keys using publicly disclosed or previously compromised keys.
- Encrypt files using SSE-C using an AES-256 encryption key that is generated and stored locally.
- Set lifecycle policies for file deletion, marking them at 7 days using the S3 Object Lifecycle Management API to add urgency to the ransom demand.
- Deposit a ransom note in each affected directory, warning that any changes to the account’s permissions or files will end the negotiation.
Amazon Ransomware’s Impossible Recovery Highlights Difficulties in Making Ransom Payments Illegal
As news of the UK Home Office’s plans to make ransomware payments to some victims illegal, particularly companies and national infrastructure services, security experts have come out with their opinions on such a move. Given that Amazon’s attack makes it impossible to recover without paying a ransom issue on the incident response table, such laws are far from simple. “The topic of ransomware payments is hotly debated,” said Javvad Malik, chief security awareness advocate at KnowBe4, “while almost everyone agrees that ransomware payments are not desirable and organizations do not want to contribute to cybercrime or state-sponsored activities.” But mandating by law that ransoms are illegal is the best thing: “People usually want to do the right thing,” Malik said, “no executive willingly set up their organization to become a victim of ransomware, but when he strikes, and. As pressure starts to mount from shareholders, customers and the government, the temptation to pay the ransom continues to rise, unless alternative ways are provided.” This is where the government needs to work together with organizations to minimize disruption from ransomware, Mailk concluded, ” or at least provide broad guidance on how to prevent, detect, respond to, and recover from ransomware attacks.”
Amazon Statement Regarding Codefinger Ransomware Attacks
An Amazon Web Services spokesperson provided the following statement: “AWS helps customers secure their cloud resources through a shared responsibility model. Whenever AWS is aware of exposed keys, we notify affected customers. We also thoroughly investigate all reports of exposed keys and quickly take any necessary action, such as applying quarantine policies to minimize risks to customers without disrupting their IT environment. We encourage all customers to follow security, identity and compliance best practices. In case a customer suspects that they may have exposed their credentials, they can start by following the steps listed in this post. As always, customers can contact AWS Support with any questions or concerns about the security of their account.”
