Sarina

I. Targeted Entities

• Fortinet product users

II. Introduction

Multiple vulnerabilities have recently been identified in Fortinet products. These products are designed to provide network security solutions that offer protection from constantly emerging threats to your network, data, and users. (Fortiguard 2023)

III. Background Information

Fortinet has recently revealed a highly severe vulnerability, marked as “Critical,” that affects both FortiOS and FortiProxy. This flaw permits an attacker who has not been authenticated to run arbitrary code or conduct a denial-of-service (DoS) attack on the graphical user interface (GUI) of the affected systems by employing specially designed requests. (Toulas, 2023)

The vulnerability is recognized as CVE-2023-25610 and has obtained a CVSS v3 score of 9.3, which is classified as critical. A buffer underflow vulnerability like this occurs when a program attempts to read more data from a memory buffer than is available. This leads to accessing adjacent memory locations, potentially resulting in unstable behavior or system crashes. Fortinet’s telemetry data revealed no evidence that threat actors exploited the vulnerability in real-world attacks. (Multiple Vulnerabilities in Fortinet Products Could Allow for Arbitrary Code 2023)

According to Fortinet’s security bulletin, there are fifty device models that are not affected by the arbitrary code execution aspect of the vulnerability. However, these same models are still vulnerable to the denial-of-service part, even if they are running a vulnerable version of FortiOS. (Toulas, 2023)

Affected Products:

FortiOS version 7.2.0 through 7.2.3

FortiOS version 7.0.0 through 7.0.9

FortiOS version 6.4.0 through 6.4.11

FortiOS version 6.2.0 through 6.2.12

FortiOS 6.0 all versions

FortiProxy version 7.2.0 through 7.2.2

FortiProxy version 7.0.0 through 7.0.8

FortiProxy version 2.0.0 through 2.0.12

FortiProxy 1.2 all versions

FortiProxy 1.1 all versions

For those who cannot apply the updates immediately, Fortinet recommends either disabling the HTTP/HTTPS administrative interface or restricting the IP addresses that can access it remotely. Instructions on how to implement these workarounds, which also apply to non-default port usage, are provided in the security advisory.

Threat actors are actively searching for critical-severity vulnerabilities in Fortinet products, particularly those that do not require authentication to exploit. These vulnerabilities provide attackers with a means of gaining initial access to corporate networks. As a result, it is critical to quickly address this vulnerability. (Toulas, 2023)

IV. Updated Information and CVE’s in Relation with Observed Fortinet Vulnerabilities

According to an article published by Bleeping Computer on March 15, 2023, a new vulnerability in FortiOS, the operating system of Fortinet firewalls, is being actively exploited in the wild to attack government networks. The vulnerability, designated as CVE-2023-41328, is a zero-day vulnerability, meaning that it was unknown to the vendor and the public before being exploited by threat actors.

The attack appears to be highly targeted, aimed at specific government agencies. The attackers used the vulnerability to gain access to the victim’s network and install a backdoor that allowed them to exfiltrate data and execute commands on the compromised systems.

Fortinet has released a patch for the vulnerability and is urging all customers to update their systems immediately. The company has also stated that it is working closely with law enforcement and other relevant authorities to investigate the attacks and identify the perpetrators.

• CVE-2022-41328 – FortiOS – Path traversal in execute command
• CVE-2022-39951 – FortiWeb – command injection in webserver: An improper neutralization of special elements used in an OS command vulnerability in FortiWeb may allow authenticated users to execute unauthorized code or commands via specifically crafted HTTP requests.
• CVE-2022-39953 – FortiNAC – Multiple privilege escalation via sudo command: An improper privilege management vulnerability in FortiNAC may allow a low privilege local user with shell access to execute arbitrary commands as root.
• CVE-2022-40676 – FortiNAC – Multiple Reflected XSS: An improper neutralization of input during web page generation in FortiNAC may allow an authenticated user to perform an XSS attack via crafted HTTP requests.
• CVE-2023-25605 – FortiSOAR – Improper Authorization in request headers: An improper access control vulnerability in FortiSOAR’s playbook component may allow an attacker authenticated on the administrative interface to perform unauthorized actions via crafted HTTP requests.
• CVE-2022-42476 – FortiOS / FortiProxy – Path traversal vulnerability allows VDOM escaping: A relative path traversal vulnerability in FortiOS and FortiProxy may allow privileged VDOM administrators to escalate their privileges to super admin of the box via crafted CLI requests.

V. MITRE ATT&CK

• T1190 – Exploit Public-Facing Application
  Adversaries may attempt to take advantage of a weakness in an Internet-facing computer or program using software, data, or commands to cause unintended or unanticipated behavior. The weakness in the system can be a bug, a glitch, or a design vulnerability. These applications are often websites, but can include databases (like SQL), standard services (like SMB or SSH), network device administration and management protocols (like SNMP and Smart Install), and any other applications with Internet accessible open sockets, such as web servers and related services.
• T1499 – Endpoint Denial-Of-Service
  Adversaries may perform Endpoint Denial of Service (DoS) attacks to degrade or block the availability of services to users. Endpoint DoS can be performed by exhausting the system resources those services are hosted on or exploiting the system to cause a persistent crash condition.

V. Recommendations From the Center for Internet Security (MS-ISAC)

• Safeguard 7.1: Establish and Maintain a Vulnerability Management Process:
  Establish and maintain a documented vulnerability management process for enterprise assets. Review and update documentation annually, or when significant enterprise changes occur that could impact this Safeguard.
• Safeguard 7.2: Establish and Maintain a Remediation Process:
  Establish and maintain a risk-based remediation strategy documented in a remediation process, with monthly, or more frequent, reviews.
• Safeguard 7.3: Perform Automated Operating System Patch Management:
  Perform operating system updates on enterprise assets through automated patch management on a monthly, or more frequent, basis.
• Safeguard 7.4: Perform Automated Application Patch Management:
  Perform application updates on enterprise assets through automated patch management on a monthly, or more frequent, basis.
• Safeguard 7.6: Perform Automated Vulnerability Scans of Externally Exposed Enterprise Assets:
  Perform automated vulnerability scans of externally-exposed enterprise assets using a SCAP-compliant vulnerability scanning tool. Perform scans on a monthly, or more frequent, basis.
• Safeguard 7.7: Remediate Detected Vulnerabilities:
  Remediate detected vulnerabilities in software through processes and tooling on a monthly, or more frequent, basis, based on the remediation process.
• Safeguard 12.1: Ensure Network Infrastructure is Up-to-Date:
  Ensure network infrastructure is kept up-to-date. Example implementations include running the latest stable release of software and/or using currently supported network-as-a-service (NaaS) offerings. Review software versions monthly, or more frequently, to verify software support.
• Safeguard 18.1: Establish and Maintain a Penetration Testing Program:
  Establish and maintain a penetration testing program appropriate to the size, complexity, and maturity of the enterprise. Penetration testing program characteristics include scope, such as network, web application, Application Programming Interface (API), hosted services, and physical premise controls; frequency; limitations, such as acceptable hours, and excluded attack types; point of contact information; remediation, such as how findings will be routed internally; and retrospective requirements.
• Safeguard 18.2: Perform Periodic External Penetration Tests:
  Perform periodic external penetration tests based on program requirements, no less than annually. External penetration testing must include enterprise and environmental reconnaissance to detect exploitable information. Penetration testing requires specialized skills and experience and must be conducted through a qualified party. The testing may be clear box or opaque box.
• Safeguard 18.3: Remediate Penetration Test Findings:
  Remediate penetration test findings based on the enterprise’s policy for remediation scope and prioritization. Vulnerability scanning is used to find potentially exploitable software vulnerabilities to remediate them. (M1016: Vulnerability Scanning)
• Safeguard 16.13: Conduct Application Penetration Testing:
  Conduct application penetration testing. For critical applications, authenticated penetration testing is better suited to finding business logic vulnerabilities than code scanning and automated security testing. Penetration testing relies on the skill of the tester to manually manipulate an application as an authenticated and unauthenticated user.
• Apply the Principle of Least Privilege to all systems and services. Run all software as a non-privileged user (one without administrative privileges) to diminish the effects of a successful attack. (M1026: Privileged Account Management)
• Safeguard 4.7: Manage Default Accounts on Enterprise Assets and Software:
  Manage default accounts on enterprise assets and software, such as root, administrator, and other pre-configured vendor accounts. Example implementations can include disabling default accounts or making them unusable.
• Safeguard 5.4: Restrict Administrator Privileges to Dedicated Administrator Accounts:
  Restrict administrator privileges to dedicated administrator accounts on enterprise assets. Conduct general computing activities, such as internet browsing, email, and productivity suite use, from the user’s primary, non-privileged account.
• Safeguard 5.5: Establish and Maintain an Inventory of Service Accounts:
  Establish and maintain an inventory of service accounts. The inventory, at a minimum, must contain department owner, review date, and purpose. Perform service account reviews to validate that all active accounts are authorized, on a recurring schedule at a minimum quarterly, or more frequently.
• Safeguard 6.8: Define and Maintain Role-Based Access Control:
  Define and maintain role-based access control, through determining and documenting the access rights necessary for each role within the enterprise to successfully carry out its assigned duties. Perform access control reviews of enterprise assets to validate that all privileges are authorized, on a recurring schedule at a minimum annually, or more frequently.
• Architect sections of the network to isolate critical systems, functions, or resources. Use physical and logical segmentation to prevent access to potentially sensitive systems and information. Use a DMZ to contain any internet-facing services that should not be exposed from the internal network. Configure separate virtual private cloud (VPC) instances to isolate critical cloud systems. (M1030: Network Segmentation)
• Safeguard 12.2: Establish and Maintain a Secure Network Architecture:
  Establish and maintain a secure network architecture. A secure network architecture must address segmentation, least privilege, and availability, at a minimum. Restrict execution of code to a virtual environment on or in transit to an endpoint system. (M1048: Application Isolation and Sandboxing)
• Safeguard 16.8: Separate Production and Non-Production Systems:
  Maintain separate environments for production and non-production systems. Use capabilities to detect and block conditions that may lead to or be indicative of a software exploit occurring. (M1050: Exploit Protection)
• Safeguard 10.5: Enable Anti-Exploitation Features:
  Enable anti-exploitation features on enterprise assets and software, where possible, such as Microsoft® Data Execution Prevention (DEP), Windows® Defender Exploit Guard (WDEG), or Apple® System Integrity Protection (SIP) and Gatekeeper™.
• Restrict use of certain websites, block downloads/attachments, block Javascript, restrict browser extensions, etc. (M1021: Restrict Web-Based Content)
• Safeguard 9.2: Use DNS Filtering Services:
  Use DNS filtering services on all enterprise assets to block access to known malicious domains.
• Safeguard 9.3: Maintain and Enforce Network-Based URL Filters:
  Enforce and update network-based URL filters to limit an enterprise asset from connecting to potentially malicious or unapproved websites. Example implementations include category-based filtering, reputation-based filtering, or using block lists. Enforce filters for all enterprise assets.
• Safeguard 9.6: Block Unnecessary File Types:
  Block unnecessary file types attempting to enter the enterprise’s email gateway. Inform and educate users regarding the threats posed by hypertext links contained in emails or attachments especially from un-trusted sources. Remind users not to visit un-trusted websites or follow links provided by unknown or un-trusted sources. (M1017: User Training)
• Safeguard 14.1: Establish and Maintain a Security Awareness Program:
  Establish and maintain a security awareness program. The purpose of a security awareness program is to educate the enterprise’s workforce on how to interact with enterprise assets and data in a secure manner. Conduct training at hire and, at a minimum, annually. Review and update content annually, or when significant enterprise changes occur that could impact this Safeguard.
• Safeguard 14.2: Train Workforce Members to Recognize Social Engineering Attacks:
  Train workforce members to recognize social engineering attacks, such as phishing, pre-texting, and tailgating.

VII. References

• Toulas, B. (2023, March 8). Fortinet warns of New Critical unauthenticated RCE vulnerability. BleepingComputer. Retrieved March 13, 2023, from https://www.bleepingcomputer.com/news/security/fortinet-warns-of-new-critical-unauthenticated-rce-vulnerability/
• Fortiguard. FortiGuard. (n.d.). Retrieved March 13, 2023, from https://www.fortiguard.com/psirt-monthly-advisory/march-2023-vulnerability-advisories
• Fortiguard. FortiGuard. (n.d.). Retrieved March 13, 2023, from https://www.fortiguard.com/psirt/FG-IR-23-001
• Endpoint denial of service. Endpoint Denial of Service, Technique T1499 – Enterprise | MITRE ATT&CK®. (n.d.). Retrieved March 13, 2023, from https://attack.mitre.org/techniques/T1499/
• Exploit public-facing application. Exploit Public-Facing Application, Technique T1190 – Enterprise | MITRE ATT&CK®. (n.d.). Retrieved March 13, 2023, from https://attack.mitre.org/techniques/T1190/
• Recorded future: Securing our world with intelligence. Recorded Future: Securing Our World With Intelligence. (n.d.). Retrieved March 13, 2023, from https://www.recordedfuture.com/
• (2023, March 8). MS-ISAC CYBERSECURITY ADVISORY – Multiple Vulnerabilities in Fortinet Products Could Allow for Arbitrary Code Execution – PATCH NOW – TLP: CLEAR.

Threat Advisory created by The Cyber Florida Security Operations Center. Contributing Security Analysts: EJ Bulut

I. Targeted Entities

• Opportunistic (any industry)

II. Introduction

RedLine Stealer is a malware family written in C# that harvests autocomplete data, such as saved credentials and financial information, from web browsers. It can also steal system information such as location, hardware configuration, and security software data.

III. Background Information

Redline Stealer (RLS) is a popular piece of malware that operates on a malware-as-a-service (MaaS) model and is sold through underground forums for approximately $100 (Unnikrishnan). Cyber criminals are able to use this software to gather a vast range of sensitive data from Gecko-based and Chromium-based web browsers. This data includes saved credentials, financial information, and cookies, which allow attackers to access various accounts ranging from social media to cryptocurrency wallets (Meskauskas).

Telemetry data, collected by CloudSEK, has picked up deployment of RLS via Regsvcs.exe on Windows systems. The content of the Regsvcs.exe process, in suspended state, is replaced by the loader using a process hollowing technique. This allows for the portable executable of RLS to be mapped into the Regsvcs.exe process, where thread contexts can be manipulated to point to RLS’s entry location. Once complete, RLS is able to masquerade as a legitimate process on the system (Unnikrishnan).

Fake software posing as legitimate software is often used to spread malware like RLS, and eSentire’s Threat Response Unit (eTRU) has observed such a case where RLS is being distributed via a fake version of AnyDesk (eSentire). The legitimate version of AnyDesk’s website was copied to a malicious website, where a victim would download an installer as an ISO image file that has been padded with junk data. This padding is done to bypass file size limitations imposed by sandboxes and antiviruses (eSentire). Once the victim runs the installer, several commands are executed to run obfuscated files that check for antivirus software, communicate with the attacker’s command-and-control servers, and read the victim’s data (eSentire).

RLS comes with several more features other than stealing data like saved passwords. Its primary targets are the user’s desktop and documents directories, where it looks for cryptocurrency data, like crypto wallets, through more than 40 browser extensions. It captures a screenshot of the desktop, as well as collects Discord tokens and user data from the Steam. Beyond financial data, RLS can retrieve system information such as username, processor and memory information, installed browsers and antivirus programs, and currently running processes (Unnikrishnan).

IV. Cyber Florida SOC Operations

After initial malware execution, Cyber Florida has observed multiple executables dropped by a self-extracting RAR file. These executables, 123.exe and 321.exe work together to create two vbc.exe child processes to carry out the malicious code. The process vbc.exe appears to attempt communication with targeted IP addresses and ports and with one of those communications, Cyber Florida observed what appeared to be the creation of “bebra.exe” but upon a hex content review of the file, only the ASCII string “Hello” was present. It is suspected that this process may be attempting to establish some sort of communication and then leads to a program crash by design. A hypothesis is that the “bebra.exe” file may just be a place holder until actual binary content is needed or wanted by the malware. A review of vbc.exe appears to be a legitimate binary that may have been abused and injected into. Vbc.exe is known as the Visual Basic Compiler and used with the .Net Framework. The tactic of injecting into a known good process may be a way for an attacker’s malware to evade detection. The vbc.exe processes did have portions of memory that had RWX (Read, Write, and Execute) permissions. These sections of memory did have binary content and those were extracted and analyzed. Cyber Florida uploaded both files to VirusTotal and the following binary file was already detected:

https://www.virustotal.com/gui/file/a82732b71779c41df6b105ffe98f385b53d6bd64d783d6cb3caac9be3270d783/details

However, the following was not seen on VirusTotal until Cyber Florida uploaded the file for review:

https://www.virustotal.com/gui/file/f179a2d8bc7ab6cd32a8c1f95988d77fb1381072ac92f099047f7395cae84115

Network Traffic

This communication was the first observed network connection from the victim system to a potential attacker-controlled system. The communication was to 65.21.213.208:3000. The TCP stream below shows a POST action to the system with no real content. The server replies back with a “Hello” response. Of interest the “bebra.exe” file identified in the victim’s AppData/Roaming folder was not a binary of any sort and when viewed in a hex editor only had an ASCII string of “Hello”. Also, of interest with “bebra.exe” is that the Content-Type was of application/x-msdownload, which would be associated with a binary file.

The following communication was the second observed network connection from the victim system to a potential attacker-controlled system. The traffic was to 51.89.207.166:47909. The observed traffic appeared to have no successful connections made. However, this IP and specified port have been identified as potentially malicious through other threat intelligence sources.

Similar Observations Seen From ArechClient2

In November 2022, the Cyber Florida SOC released a threat advisory on Arechclient2, and provided presentations on their analysis. During analysis of Arechclient2 a Base64 string containing, once de-obfuscated, various Chrome extensions associated to Crypto wallets. Arechclient2 and RedLine appear to have similar functionality such as stealing browser data like usernames, passwords, and other related content such as information related to crypto wallets. When analyzing the current version of RedLine a similar Base64 string was found. The following string is base64 encoded data and the decoded results, via CyberChef. This further shows similarity between the two malware variants.

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N8VGVtcGxlV2FsbGV0

ffnbelfdoeiohenkjibnmadjiehjhajb|YoroiWallet
ibnejdfjmmkpcnlpebklmnkoeoihofec|Tronlink
jbdaocneiiinmjbjlgalhcelgbejmnid|NiftyWallet
nkbihfbeogaeaoehlefnkodbefgpgknn|Metamask
afbcbjpbpfadlkmhmclhkeeodmamcflc|MathWallet
hnfanknocfeofbddgcijnmhnfnkdnaad|Coinbase
fhbohimaelbohpjbbldcngcnapndodjp|BinanceChain
odbfpeeihdkbihmopkbjmoonfanlbfcl|BraveWallet
hpglfhgfnhbgpjdenjgmdgoeiappafln|GuardaWallet
blnieiiffboillknjnepogjhkgnoapac|EqualWallet
cjelfplplebdjjenllpjcblmjkfcffne|JaxxxLiberty
fihkakfobkmkjojpchpfgcmhfjnmnfpi|BitAppWallet
kncchdigobghenbbaddojjnnaogfppfj|iWallet
amkmjjmmflddogmhpjloimipbofnfjih|Wombat
fhilaheimglignddkjgofkcbgekhenbh|AtomicWallet
nlbmnnijcnlegkjjpcfjclmcfggfefdm|MewCx
nanjmdknhkinifnkgdcggcfnhdaammmj|GuildWallet
nkddgncdjgjfcddamfgcmfnlhccnimig|SaturnWallet
fnjhmkhhmkbjkkabndcnnogagogbneec|RoninWallet
aiifbnbfobpmeekipheeijimdpnlpgpp|TerraStation
fnnegphlobjdpkhecapkijjdkgcjhkib|HarmonyWallet
aeachknmefphepccionboohckonoeemg|Coin98Wallet
cgeeodpfagjceefieflmdfphplkenlfk|TonCrystal
pdadjkfkgcafgbceimcpbkalnfnepbnk|KardiaChain
bfnaelmomeimhlpmgjnjophhpkkoljpa|Phantom
fhilaheimglignddkjgofkcbgekhenbh|Oxygen
mgffkfbidihjpoaomajlbgchddlicgpn|PaliWallet
aodkkagnadcbobfpggfnjeongemjbjca|BoltX
kpfopkelmapcoipemfendmdcghnegimn|LiqualityWallet
hmeobnfnfcmdkdcmlblgagmfpfboieaf|XdefiWallet
lpfcbjknijpeeillifnkikgncikgfhdo|NamiWallet
dngmlblcodfobpdpecaadgfbcggfjfnm|MaiarDeFiWallet
ffnbelfdoeiohenkjibnmadjiehjhajb|YoroiWallet
ibnejdfjmmkpcnlpebklmnkoeoihofec|Tronlink
jbdaocneiiinmjbjlgalhcelgbejmnid|NiftyWallet
nkbihfbeogaeaoehlefnkodbefgpgknn|Metamask
afbcbjpbpfadlkmhmclhkeeodmamcflc|MathWallet
hnfanknocfeofbddgcijnmhnfnkdnaad|Coinbase
fhbohimaelbohpjbbldcngcnapndodjp|BinanceChain
odbfpeeihdkbihmopkbjmoonfanlbfcl|BraveWallet
hpglfhgfnhbgpjdenjgmdgoeiappafln|GuardaWallet
blnieiiffboillknjnepogjhkgnoapac|EqualWallet
cjelfplplebdjjenllpjcblmjkfcffne|JaxxxLiberty
fihkakfobkmkjojpchpfgcmhfjnmnfpi|BitAppWallet
kncchdigobghenbbaddojjnnaogfppfj|iWallet
amkmjjmmflddogmhpjloimipbofnfjih|Wombat
fhilaheimglignddkjgofkcbgekhenbh|AtomicWallet
nlbmnnijcnlegkjjpcfjclmcfggfefdm|MewCx
nanjmdknhkinifnkgdcggcfnhdaammmj|GuildWallet
nkddgncdjgjfcddamfgcmfnlhccnimig|SaturnWallet
fnjhmkhhmkbjkkabndcnnogagogbneec|RoninWallet
aiifbnbfobpmeekipheeijimdpnlpgpp|TerraStation
fnnegphlobjdpkhecapkijjdkgcjhkib|HarmonyWallet
aeachknmefphepccionboohckonoeemg|Coin98Wallet
cgeeodpfagjceefieflmdfphplkenlfk|TonCrystal
pdadjkfkgcafgbceimcpbkalnfnepbnk|KardiaChain
bfnaelmomeimhlpmgjnjophhpkkoljpa|Phantom
fhilaheimglignddkjgofkcbgekhenbh|Oxygen
mgffkfbidihjpoaomajlbgchddlicgpn|PaliWallet
aodkkagnadcbobfpggfnjeongemjbjca|BoltX
kpfopkelmapcoipemfendmdcghnegimn|LiqualityWallet
hmeobnfnfcmdkdcmlblgagmfpfboieaf|XdefiWallet
lpfcbjknijpeeillifnkikgncikgfhdo|NamiWallet
dngmlblcodfobpdpecaadgfbcggfjfnm|MaiarDeFiWallet
bhghoamapcdpbohphigoooaddinpkbai|Authenticator
ookjlbkiijinhpmnjffcofjonbfbgaoc|TempleWallet

Inject VBC 1 Process

The following shows metadata associated to the injected binary for the first VBC process. Of note is essentially the future timestamp value of the binary. Also reviewing some of content statically, did not reveal as much data as dynamic did. For example, attacker IP addresses and other key findings were not identified in a static manner. The binary appears to have been compiled in .NET and the source code of the injected binary would be the next step for analysis.

The following string was extracted from ProcessHacker as the malware was running. This string shows the IP address and specified port of interest, along with the POST action observed in Wireshark. This activity also lines up with the ProcMon (ProcessMonitor) logs that were generated from this activity.

Inject VBC 2 Process

The following shows metadata associated to the injected binary for the second VBC process. Of note is essentially the no timestamp value of the binary. Also reviewing some of content statically, did not reveal as much data as dynamic did. For example, attacker IP addresses and other key findings were not identified in a static manner.

The following screenshots were taken from ProcessHacker as the malware was running. We can observe the IP address and specified port of interest as strings and represented as Base64 as well.

Overall Order of VBC Activity

The following is a brief high-level (non-exhaustive) order  of activity as it relates to vbc.exe execution of malicious activity. Taken from ProcMon logs.

V. MITRE ATT&CK

• T1005 – Data from Local System
  Adversaries may search local system sources, such as file systems and configuration files or local databases, to find files of interest and sensitive data prior to Exfiltration. Adversaries may do this using a Command and Scripting Interpreter, such as cmd as well as a Network Device CLI, which have functionality to interact with the file system to gather information. Adversaries may also use Automated Collection on the local system.
• T1012 – Query Registry
  Adversaries may interact with the Windows Registry to gather information about the system, configuration, and installed software. The Registry contains a significant amount of information about the operating system, configuration, software, and security.[1] Information can easily be queried using the Reg utility, though other means to access the Registry exist. Some of the information may help adversaries to further their operation within a network. Adversaries may use the information from Query Registry during automated discovery to shape follow-on behaviors, including whether or not the adversary fully infects the target and/or attempts specific actions.
• T1552.001 – Unsecured Credential; Credentials in Files
  Adversaries may attempt to take screen captures of the desktop to gather information over the course of an operation. Screen capturing functionality may be included as a feature of a remote access tool used in post-compromise operations. Taking a screenshot is also typically possible through native utilities or API calls.
• T1082 – System Discovery
  An adversary may attempt to get detailed information about the operating system and hardware, including version, patches, hotfixes, service packs, and architecture. Adversaries may use the information from System Information Discovery during automated discovery to shape follow-on behaviors, including whether or not the adversary fully infects the target and/or attempts specific actions.
• T1055 – Process Injection
  Adversaries may inject code into processes in order to evade process-based defenses as well as possibly elevate privileges. Process injection is a method of executing arbitrary code in the address space of a separate live process. Running code in the context of another process may allow access to the process’s memory, system/network resources, and possibly elevated privileges. Execution via process injection may also evade detection from security products since the execution is masked under a legitimate process.
• T1095 –Non-Application Layer Protocol
  Adversaries may use a non-application layer protocol for communication between host and C2 server or among infected hosts within a network. The list of possible protocols is extensive
• T1059 – Command and Scripting Interpreter
  Adversaries may abuse command and script interpreters to execute commands, scripts, or binaries. These interfaces and languages provide ways of interacting with computer systems and are a common feature across many different platforms. Most systems come with some built-in command-line interface and scripting capabilities, for example, macOS and Linux distributions include some flavor of Unix Shell while Windows installations include the Windows Command Shell and PowerShell.

VI. Recommendations

• Phishing awareness training
  Users should be informed and educated about new kinds of phishing scams currently being used and ones that have been used in the past. Awareness training should instruct users to avoid suspicious emails, links, websites, attachments, etc. Users should alsobe educated about new types of attacks and schemes to mitigate risk. Recommended link: https://www.us-cert.gov/ncas/tips/ST04-014
• Set antivirus programs to conduct regular scans
  Ensure that antivirus and antimalware programs are scanning assets using up-to-date signatures
• Malware monitoring
  Continuously monitor current and new types of malware. Stay up to date on intel and advancements to prevent, defend, and mitigate these types of threats.
• Strong cyber hygiene
  Enforce a strong password policy across all networks and subsystems. Remind users to be wary of any messages asking for immediate attention, links, downloads, etc. All sources should be verified. Recommended link: https://us-cert.cisa.gov/ncas/alerts/aa21-131a
• Turn on endpoint protection
  Enable endpoint detection and response (EDR) to stop unknown malware in the product you’re using.
• Network Monitoring
  Review network logs, payload, etc. for related IP addresses and associated network parameters.

VII. Indicators of Compromise (IOCs)

VII. Additional OSINT Information

4efdf3a4c19a94b2e58f5212124cb161.exe
Note: the initial executable may have a different file name.

123.exe
https://www.virustotal.com/gui/file/d3b64baa18214715f544c836b59e2ca839e86 95f93706476033a1e8c56dd7287

321.exe
https://www.virustotal.com/gui/file/aadbf6b7fd77075e6355a209c4cbd8b1049f21eb69f503203bd6fd7a7a085dc6

Vbc.exe.bin (injected 1 process)
https://www.virustotal.com/gui/file/a82732b71779c41df6b105ffe98f385b53d6bd64d783d6cb3caac9be3270d783

Vbc.exe2.bin (injected 2 process)
https://www.virustotal.com/gui/file/f179a2d8bc7ab6cd32a8c1f95988d77fb1381072ac92f099047f7395cae84115?nocache=1

IX. References

eSentire. Esentire Threat Intelligence Malware Analysis: Redline Stealer. eSentire. (n.d.). Retrieved February 10, 2023, from https://www.esentire.com/blog/esentire-threat-intelligence-malware-analysis-redline-stealer

Meskauskas, T. (2023, February 1). Redline Stealer malware. RedLine Stealer Malware – Malware removal instructions (updated). Retrieved February 10, 2023, from https://www.pcrisk.com/removal-guides/17280-redlinestealer-malware

Unnikrishnan, A., & CloudSEk. (2023, January 26). Technical analysis of the redline stealer: CloudSEK. RSS. Retrieved February 10, 2023, from https://cloudsek.com/blog/technical-analysis-of-the-redline-stealer

Threat Advisory created by The Cyber Florida Security Operations Center. Contributing Security Analysts: Sreten Dedic, EJ Bulut

To learn more about Cyber Florida visit: www.cyberflorida.org