Article
Ransomware Decryptors for a (varying) fee
Arete Analysis
Ransomware attacks wreak havoc on business operations. Destroying recovery options, instilling fear and panic, and most often creating high levels of stress for IT staff, owners, and operators. A simple, but often costly fix is to just pay the Threat Actor for the decryption utility. While making a payment to an anonymous entity is a highly debated topic, let us assume, for the purposes of this article, that the payment is the only option other than closing your business. Please note, Arete is not advocating to pay ransoms; the choice is entirely a business decision to pursue. This article is intended to provide insight into the various types of decryptors the threat groups provide to unlock your files. We will discuss specific decryptors for some of the more popular variants as well as address subtle nuances between the decryptors.
Full Disk Encryption
Ransomware variants like THT, Mamba, or MCrypt use native or opensource encryption software to encrypt the entire hard drive of the system. Once the TA gains access to the system with administrator privileges, the TA will use a tool like Bestcrypt, DiskCryptor or even Windows Bitlocker to encrypt the full disk. Once encryption is complete, the system reboots and the victims are locked out.
Communication preference: Email usually protonmail, firemail.cc, or cock.li domains
Average ransom payment: $36,000 – $55,000
Preferred currency: Bitcoin (BTC)
Decryptor received: 100% of the time. TA will provide passwords per system for access
Watch out: MCrypt will hold volumes hostage and “re-extort” victims into making multiple payments. During the initial negotiation, the TA will not indicate multiple drives are encrypted. Instead they will negotiate a single amount for initial access to the Operating System; essentially allowing access into Windows. Once access to Windows is regained, victims often surprised to find their “data” partitions are encrypted causing the victim to return to the negotiation table to once again shell out more money to unlock their information.
Notes: After gaining access, the open source encryption tool still needs to be removed otherwise after reboot, the data storage will be locked again.
System Specific Encryption
Ransomware variants like Phobos, Dharma or CryLock are file level encryption. The TA gains access to the system, copies specific encryption executables onto the systems then runs the executables to encrypt the files. The results are files with a new extension appended to the old file name. Sometimes it’s a random sequence of numbers and letters (e.g. *.nocv) or a specific tag (e.g. *[CryLockDecrypt@****.com][1].[ID-*****- COM]). System specific encryption generates a unique key per encrypted system. The ransom note or the file extension may indicate an “ID” that would be different on each system.
CryLock Scanner & Decryptor
Communication preference: Email usually aol.com, protonmail.com, or cock.li domains
Average ransom payment: $27,000 – $500,000
Preferred currency: Bitcoin (BTC)
Decryptor Received: 95% of the time. Certain variants of Phobos and Dharma will attempt to re-extort a second payment if a large discount is negotiated.
Watch out: Phobos, Dharma, and CryLock are a two-step process. The TA will first send a “scanner” tool that needs to be run on every infected system. The scanner will look for the public keys used to encrypt the files, then write that information to a corresponding .txt or .ini file. Those corresponding files need to be sent to the TA in order to generate a decryptor. The TA in return will send the decryptors. The two-step process adds significant overhead due to the running of multiple tools on the infected system as well as the delay with communicating via email. On average after making a payment for the decryptor, clients are who are infected with Phobos are down for approximately 11 days whereas clients who are infected with Dharma experience downtime of about 7.75 days. The high number of days can be attributed to the two-step process and multiple email communications.
Notes: Negotiating with the Phobos and Dharma group can be tricky. These variants are Ransom-as-a-Service (RaaS) model so you’re not dealing with the same core group of people as you would with variants like Ryuk (or now Conti). Negotiating with RaaS groups can also create confusion and complexities with a different operator responding to each email. The groups who deploy these variants also look for exploiting publicly accessible Remote Desktop Protocol (RDP). Disable external access to RDP to lessen the chance of being infected by this variant.
System Specific Encryption with a Universal Option
Ransomware variants like Sodinokibi are file level encryption with a unique ID per system. Once the TA gains access to the network, they release their Sodinokibi ransomware throughout the environment. The systems are infected with a unique randomly generated file extension per system. Their ransom notes are usually within a text file and explain what happened, including if any data was exfiltrated. The group is very organized and can often share information about their victim’s networks including domain information, infected systems, and any stolen data.
Sodinokibi Decryptor
Communication preference: TOR Website via chat room. The ransom note contains a link to the TOR site as well as a unique key to gain access to a private chat room where the negotiations occur.
Average ransom payment: $170,000
Preferred currency: Monero (XMR)
Decryptor received: 100% of the time. Sodin offers a general decryptor which requires the victim to collect the file extensions from all of their infected systems. This can be very tedious once the payment is made, the victim can input any number of file extensions into the input box on the TOR site to generate a decryptor. Sodin will keep that private room open for 30 days after payment allowing victims to return if they find any extensions not previously found. A lesser known secret with Sodin, if you ask nicely for a universal decryptor, the operator may create the decryptor for you; providing a single decryptor that can be used across your network. The universal decryptor certainly saves a lot of time with decrypting files and minimizing the number of times having to launch the TOR browser.
Watch out: Earlier this year, Sodin changed their code base for their encryption payloads causing instability on certain Windows Operating Systems within the master boot files. Using certain security tools after a Sodin outbreak can cause systems to hang during reboot. Sodin encryption is one of the more aggressive encryptions.
Be sure to create a snapshot or backup the files prior to installing any new software or performing live forensics on critical systems.
Notes: Sodin has made headlines throughout 2020 for following Maze with exfiltrating data as well as being the first ransomware group to only accept Monero for payments.
System Specific Encryption with a Universal Option
Ransomware variants like Sodinokibi are file level encryption with a unique ID per system. Once the TA gains access to the network, they release their Sodinokibi ransomware throughout the environment. The systems are infected with a unique randomly generated file extension per system. Their ransom notes are usually within a text file and explain what happened, including if any data was exfiltrated. The group is very organized and can often share information about their victim’s networks including domain information, infected systems, and any stolen data.
Sodinokibi Decryptor
Communication preference: TOR Website via chat room. The ransom note contains a link to the TOR site as well as a unique key to gain access to a private chat room where the negotiations occur.
Average ransom payment: $170,000
Preferred currency: Monero (XMR)
Decryptor received: 100% of the time. Sodin offers a general decryptor which requires the victim to collect the file extensions from all of their infected systems. This can be very tedious once the payment is made, the victim can input any number of file extensions into the input box on the TOR site to generate a decryptor. Sodin will keep that private room open for 30 days after payment allowing victims to return if they find any extensions not previously found. A lesser known secret with Sodin, if you ask nicely for a universal decryptor, the operator may create the decryptor for you; providing a single decryptor that can be used across your network. The universal decryptor certainly saves a lot of time with decrypting files and minimizing the number of times having to launch the TOR browser.
Watch out: Earlier this year, Sodin changed their code base for their encryption payloads causing instability on certain Windows Operating Systems within the master boot files. Using certain security tools after a Sodin outbreak can cause systems to hang during reboot. Sodin encryption is one of the more aggressive encryptions.
Be sure to create a snapshot or backup the files prior to installing any new software or performing live forensics on critical systems.
Notes: Sodin has made headlines throughout 2020 for following Maze with exfiltrating data as well as being the first ransomware group to only accept Monero for payments. eir.co
Universal Encryption
Ransomware variants like Ryuk, WastedLocker, and Dopplepaymer are also file level encryption. These groups will gain access to the network and perform reconnaissance to identify the victim, understand their business, identify critical systems, and delete backups to force their victims into making a payment. The groups can have access to the network for a few hours or upwards of over a month. Ryuk is commonly associated with precursor trojans such as Trickbot and Emotet. Arete has observed Ryuk deployed as quickly as 6 hours after a Trickbot infection. Ryuk infections result with *.ryk appended to the file name. Comparatively, the deployment of WastedLocker is much more calculated with the TA staying on the network for an average of 2 weeks from initial infection to ransomware deployment. Wasted infections result with *.abcwasted appended to the file name where “abc” is a 3 letter abbreviation relating directly to the victims name.
WastedLocker Decryptor
Communication preference: Email usually protonmail.com domains or TOR Website
Average ransom payment: Ryuk $598,000; WastedLocker $2,400,000; Dopplepaymer $304,000
Preferred currency: Bitcoin (BTC)
Decryptor received: 100% of the time. The decryptor received is universal. It is typically a 32-bit executable that will work on any windows OS version. While these groups are known for a high ransom price, their decryptor is probably the simplest to run.
Watch out: WastedLocker is extremely difficult to negotiate. In fact, if negotiation is attempted, they may threaten to increase the ransom by approximately 5% of the ransom per day until it is paid. They are also very slow to respond to email and even post their business hours of UTC 5am- 8am and 5pm-8pm.
Notes: Dopplepaymer has been linked to gaining access to large environments and deploying cryptomining malware before launching their ransomware attack.
Pro Tips to Prevent Ransomware
Attacks
Implement Endpoint, Detection, and Response software such as SentinelOne to monitor the computer systems in use by your organization. SentinelOne uses Artificial Intelligence technology to detect malicious actions and prevent them before they can severely affect the endpoint.
Leverage a Security Operations Center (“SOC”) to monitor computer systems 24 hours a day by 7 days a week. The SOC can instantly respond to triage and mitigate any alerts while keeping your IT personnel focused on maintain business productivity.
Enable Multi-Factor Authentication (“MFA”) on remote access technologies such as VPN and Email.
Use complex passwords with a minimum of 16 alphanumeric characters (non- dictionary words).
Don’t reuse passwords.
Encourage discussion about cybersecurity within the workplace including establishing end user awareness training.
Ensure backups are current, air gapped from the production network, and viable.
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Article
FortiBleed Campaign Remains Active
The FBI and Secret Service recently warned that the FortiBleed credential-harvesting campaign remains an active threat targeting internet-facing Fortinet FortiGate firewalls and secure socket layer (SSL) virtual private network (VPN) gateways. The agencies report that attackers continue to scan internet-exposed Fortinet firewalls using previously obtained credentials. This has reinforced assessments made by other security researchers, who have stated that “FortiBleed should be treated as an active access operation, not as a one-time credential leak.”
What’s Notable and Unique
FortiBleed, active since February 2026, begins with widespread reconnaissance to identify internet-facing FortiGate firewalls and SSL-VPN services. Once potential targets are identified, operators attempt to gain initial access through credential stuffing, password spraying, and dictionary attacks using previously compromised credentials.
Following successful access, the attackers deploy the Go-based FortigateSniffer tool on compromised appliances. The tool leverages native FortiOS diagnostic functionality to passively intercept authentication traffic across 24 protocols, enabling the collection of cleartext credentials and password hashes passing through the device.
Successfully recovered credentials are reused to expand access, including Active Directory enumeration, Kerberos validation, SMB authentication, and network share discovery, enabling threat actors to move deeper into the victim environment.
Reporting indicates that initial access brokers (IABs) leveraging the FortiBleed attack chain have facilitated access for downstream ransomware operations, including the INC Ransom/Lynx and Payload ransomware groups. This aligns with Arete’s observations of ransomware groups, including INC, Qilin, and DragonForce, targeting Fortinet FortiGate and VPN infrastructure as an initial access vector.
Remediation
Organizations should restrict internet-facing FortiGate management interfaces, rotate administrative and VPN credentials, review local and privileged accounts, and enforce MFA for remote access. If a potential compromise is detected, organizations should isolate affected systems, conduct threat hunting to determine the scope and identify compromised accounts and devices, and preserve relevant logs and artifacts. Organizations should also report the incident to appropriate authorities and implement targeted eviction measures based on identified threat actor activity.
Analyst Comments
FortiBleed represents an ongoing access-enablement threat, rather than a one-time credential exposure. The campaign’s ability to harvest, validate, and reuse credentials can provide sustained access to victim environments and create opportunities for downstream ransomware activity. Organizations with suspected FortiGate exposure should treat the activity as a potential active compromise and investigate for persistent access, compromised accounts, and lateral movement.
Sources
FortiBleed Operations Continue Targeting Exposed Systems Leading to Reports of Lockouts
FBI Warns FortiBleed Remains Active After Amassing 86,644 Fortinet Device Credentials
Article
Threat Actors Exploiting Critical FortiMail Zero-Day Vulnerability
Fortinet has disclosed a critical vulnerability in FortiMail, tracked as CVE-2026-104286, that is currently being exploited as a zero-day in the wild. The flaw, which carries a Critical CVSS score of 9.8, affects the FortiMail management interface and can allow unauthenticated attackers to write arbitrary files to affected systems, potentially leading to unauthorized code execution and full system compromise. Fortinet has confirmed active exploitation and urged customers to implement mitigations immediately while awaiting security updates.
What’s Notable and Unique
The vulnerability stems from improper restriction of file paths combined with improper neutralization of NULL byte characters. An unauthenticated attacker can exploit the flaw via specially crafted HTTP or HTTPS requests to write arbitrary files on the underlying operating system.
Organizations running FortiMail 7.2 can remediate the vulnerability by upgrading to 7.4 or newer. For customers using affected FortiMail 7.4, 7.6, and 8.0 versions, fixes have not yet been released. However, Fortinet has confirmed that the issue will be addressed in the upcoming 7.4.9, 7.6.7, and 8.0.2 releases.
Until the patched versions become available, Fortinet recommends mitigating risk by disabling the Identity-Based Encryption (IBE) feature. As an additional safeguard, administrators should restrict access to the FortiMail management interface, either by removing internet exposure altogether or limiting access to trusted internal networks only. The advisory also includes log entries that administrators can use to identify potentially compromised appliances.
The U.S. Cybersecurity and Infrastructure Security Agency (CISA) has added CVE-2026-104286 to its Known Exploited Vulnerabilities (KEV) catalog and directed federal agencies to perform forensic triage and mitigation by October 4th.
Analyst Comments
Impacted organizations should review their FortiMail instances to ensure there are no unauthorized logins, examine device settings, evaluate all configurations as potentially compromised, and carry out the necessary recovery procedures. Defenders should immediately implement Fortinet's recommended mitigations, review systems for IOC matches, and prepare to deploy the forthcoming security updates as soon as they become available. It is strongly advised that all enterprises assess their setups to reduce risk, as protecting publicly accessible management interfaces is a fundamental security best practice.
Sources
Improper limitation of a pathname to a restricted directory
Article
Ransomware Trends & Data Insights: September 2026
The Akira ransomware group re-emerged as the most active ransomware threat observed by Arete in September. Overall activity remained relatively distributed among multiple threat groups, with 29 unique groups observed throughout the month. Alongside Akira, INC Ransom and the relatively new Storm group were among the three most active threat actors observed in September. Several new threat groups also emerged during the month, including Hades Team, Shiba, and Vortex (which is suspected to be part of the cluster of threat actors affiliated with the former BlackFile group).
Throughout the month, analysts at Arete identified several trends behind the threat actors perpetrating cybercrime activities:
In September 2026, the ShinyHunters threat group escalated its extortion activity by publicly targeting both the Clop ransomware group and the FBI. The group claimed to have breached and defaced Clop’s infrastructure, demanding an eight-figure ransom, while separately alleging the theft of sensitive FBI-related data and demanding the retraction of statements made in a prior public advisory. In both incidents, ShinyHunters employed similar pressure tactics, including website defacements, repeated public postings, and threats of data disclosure.
ClickFix attacks remained prevalent in September 2026, with ransomware groups including Qilin, Helix, and The Gentlemen leveraging ClickFix lures to facilitate PowerShell-based payload execution and initial access. The technique continues to evolve, combining social engineering with legitimate tools and services to enable compromise and evade detection.
September 2026 saw continued activity from the former BlackFile extortion ecosystem. BlackFile, a data theft and extortion operation active since at least October 2025, rebranded as Redact in May 2026, and since appears to have broken off into several affiliated brands, including Pink, Helix, Falcon, Cinder, and potentially Vortex. During September, some affiliates publicly disputed these associations and claimed to operate independently. However, the coordinated timing, messaging, and near-identical nature of these statements support the assessment that these groups remain part of a broader interconnected ecosystem operating under shared objectives or coordination.
Article
Attack Patterns in Settra Incidents
Recent Settra ransomware incidents demonstrate a consistent operational pattern involving compromised credentials, VPN access, and the deployment of ransomware executables tailored to victim environments. Researchers have observed Settra naming ransomware executables after the targeted organization's domain while following similar attack sequences across multiple intrusions. Arete has also identified overlapping tactics, techniques, and tools in Settra engagements observed from June to August, including the use of MeshAgent for remote access and Bring Your Own Vulnerable Driver (BYOVD) techniques to weaken endpoint security controls.
What’s Notable and Unique
Settra operators have been observed naming ransomware executables after the victim organization's domain, creating a direct association between the payload and the targeted environment.
Initial access vectors have included targeting exposed VPN infrastructure and the use of compromised credentials, reducing the need for traditional exploitation of vulnerabilities.
Arete observed MeshAgent in multiple Settra engagements, which provides threat actors with a mechanism for remote access and continued activity within compromised environments.
Settra engagements have also included Bring Your Own Vulnerable Driver (BYOVD) activity, which can be used to bypass or impair security controls by abusing legitimate but vulnerable drivers.
Analyst Comments
Recent Settra activity demonstrates how ransomware operators can combine credential-based access, remote management tooling, and security control evasion techniques to establish and maintain access before ransomware deployment. The repeated use of similar tools and operational patterns across incidents provides useful detection opportunities for defenders. Organizations should closely monitor VPN authentication activity, unusual use of compromised credentials, unexpected MeshAgent deployment, ransomware executables with victim-specific naming conventions, and suspicious driver activity associated with attempts to disable or bypass endpoint security controls.
Arete’s MDR practice detects Settra’s full attack chain, with special attention to the staging of BYOVD activity for defense evasion. However, for us to detect it, SentinelOne needs to be fully deployed across an environment. To support organizations with full deployment, Arete offers SentinelOne Deployment Assistance. This service is designed to ensure that SentinelOne is deployed across all eligible endpoints, eliminating coverage gaps that could otherwise expose the organization to ransomware, malware, credential theft, and other advanced threats. Through endpoint discovery, inventory reconciliation, and deployment assistance, Arete helps organizations achieve comprehensive protection and maximize the effectiveness of their SentinelOne investment. Contact clientcares@areteir.com to learn more.
Sources
Ready, Settra, Go: New Settra Ransomware Variant Deploys MeshAgent RMM