Cisco Talos analyzed the highest 14 ransomware teams between 2023 and 2024 to show their assault chain and spotlight attention-grabbing Techniques,Strategies and Protocols. The safety firm additionally uncovered essentially the most leveraged vulnerabilities being triggered by ransomware actors.
Ransomware assault chain: What Cisco Talos researchers realized
Ransomware actors almost all use the identical assault chain.
The first step for ransomware actors
Step one for the menace actor consists of having access to the focused entity. To attain that aim, ransomware actors use totally different strategies — probably the most widespread strategies is to social engineer their targets by sending emails containing malicious information or hyperlinks that can run malware on the focused system. The malware will then enable the attacker to deploy extra instruments and malware to succeed in their objectives. Multifactor authentication is likely to be bypassed at the moment utilizing numerous strategies, both due to poor MFA implementation or due to proudly owning legitimate credentials already.
Talos additionally reported that an growing variety of ransomware associates scan internet-facing programs for vulnerabilities or misconfigurations that might enable them to compromise the system. Unpatched or legacy software program is a very excessive threat.
Step two for ransomware actors
The second step is to realize persistence in case the preliminary vector of compromise will get found; that persistence on programs is often achieved by modifying Home windows registry keys or enabling autostart execution of the malicious code upon system boot. Native, area and/or cloud accounts may additionally be created for persistence.
Step three for ransomware actors
Within the third step, the menace actor scans the community setting to get a greater understanding of the interior elements of the infrastructure. Information of worth that can be utilized for ransom is recognized at this step. To efficiently entry all elements of the community, attackers typically use instruments to raise their privileges to administrator degree, along with utilizing instruments that enable community scanning. Fashionable instruments for these duties are Residing Off the Land binaries AKA LOLbins, as a result of they’re executable information native to the working system and fewer susceptible to lift alerts.
Step 4 for ransomware actors
The attacker is able to acquire and steal delicate knowledge, which they typically compress with utilities (reminiscent of 7-Zip or WinRAR) earlier than exfiltrating the information to attacker-controlled servers by utilizing Distant Monitoring and Administration instruments or extra customized ones, reminiscent of StealBit or Exabyte for instance, created by LockBit and BlackByte ransomware teams.
Potential step 5 for ransomware actors
If the aim is knowledge theft or extortion, the operation is over. If the aim is to encrypt knowledge, the attacker wants to check the ransomware within the setting — that’s, checking the supply mechanisms and the communications between the ransomware and the C2 server — earlier than launching it to encrypt the community and notify the sufferer they’ve been breached and must pay the ransom.
Three most abused vulnerabilities
Cisco Talos reported that three vulnerabilities on public-facing functions are generally exploited by ransomware menace actors.
- CVE-2020-1472 AKA Zerologon exploits a flaw within the Netlogon Distant Protocol that permits attackers to bypass authentication and alter pc passwords inside a website controller’s Lively Listing. This exploit is extensively utilized by ransomware actors as a result of it allows them to realize entry to a community with out authentication.
- CVE-2018-13379, a Fortinet FortiOS SSL VPN vulnerability, allows path traversal that permits an attacker to entry system information by sending specifically crafted HTTP packets. VPN session tokens is likely to be accessed this fashion, which can be utilized to realize unauthenticated entry to the community.
- CVE-2023-0669, a GoAnywhere MFT vulnerability, permits attackers to execute arbitrary code on a focused server that makes use of the GoAnywhere Managed File Switch software program. That is the newest vulnerability listed by Cisco Talos in its report.
All these vulnerabilities enable ransomware actors to get preliminary entry and manipulate programs to run extra malicious payloads, set up persistence or facilitate lateral actions inside compromised networks.
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Notable TTPs of 14 ransomware teams
Cisco Talos noticed the TTPs utilized by 14 of essentially the most prevalent ransomware teams primarily based on their quantity of assault, impression to prospects and atypical conduct.
One of many key findings relating to the TTPs signifies most of the most outstanding teams prioritize establishing preliminary compromise and evading defenses of their assault chains.
Ransomware menace actors typically obfuscate their malicious code by packing and compressing it and modify the programs registry to disable safety alerts on the endpoint or server. They may additionally block sure restoration choices for the customers.
The Cisco Talos researchers highlighted that essentially the most prevalent credential entry approach is the dumping of the LSASS reminiscence contents to extract plaintext passwords, hashed passwords or authentication tokens saved in reminiscence.
One other pattern in C2 actions is using commercially accessible instruments reminiscent of RMM functions. These functions are usually trusted by the setting and permit the attacker to mix in with the company community visitors.
The best way to mitigate the ransomware menace
For starters, it’s obligatory to use patches and updates to all programs and software program; this fixed upkeep is critical to cut back the danger of being compromised by an exploit.
Strict password insurance policies and MFA have to be carried out. Advanced and distinctive passwords have to be set for each consumer and MFA enforced, so an attacker possessing legitimate credentials remains to be not in a position to entry the focused community.
Finest practices to harden all programs and environments must be utilized. Pointless providers and options needs to be disabled to cut back the assault floor. Additionally, publicity to the web have to be diminished by limiting the variety of public-facing providers as a lot as attainable.
Networks needs to be segmented utilizing VLANs or related applied sciences. Delicate knowledge and programs have to be remoted from different networks to forestall lateral actions from an attacker.
Endpoints have to be monitored by a Safety Data and Occasion Administration system, and Endpoint Detection and Response or Prolonged Detection and Response instruments must be deployed.
Disclosure: I work for Pattern Micro, however the views expressed on this article are mine.