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Mallory
MalwareUsed by 4 actorsExploits 1 CVE

BLUELIGHT

BLUELIGHT is a backdoor and basic reconnaissance/second-stage malware associated with the North Korea-linked APT37 threat actor, also known as ScarCruft, Reaper, Ricochet Chollima, and Vedalia. It has been described as a second-stage payload and was used in multistage intrusion chains, including a 2021 watering-hole attack against a South Korean online newspaper that involved an Internet Explorer exploit. In later reporting, BLUELIGHT was also observed in APT37’s 2025 Ruby Jumper campaign, where it was distributed alongside other tooling targeting air-gapped environments.

BLUELIGHT uses legitimate cloud services and multiple cloud providers for command-and-control, including Microsoft OneDrive/Graph API, Google Drive, pCloud, and BackBlaze. Reporting notes it was one of the earliest known malware families to use Microsoft Graph API/OneDrive for C2. It can exfiltrate data over its C2 channel and zip files before exfiltration.

Observed capabilities include collecting the username and local time from a compromised host, enumerating files and associated metadata, harvesting passwords stored in Internet Explorer, Edge, Chrome, and Naver Whale, harvesting cookies from Internet Explorer, Edge, Chrome, and Naver Whale, capturing screenshots every 30 seconds for the first five minutes after initiating a C2 loop and then every five minutes thereafter, and uninstalling itself. Additional reporting states BLUELIGHT can support command execution, file system enumeration, payload download and upload, and self-removal.

BLUELIGHT has also been used operationally to launch the Python loader for the more capable Dolphin backdoor on compromised systems, indicating a supporting role in APT37 espionage operations. Stairwell assessed Goldbackdoor as a successor to BLUELIGHT.

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EXPLOITED CVES

Vulnerabilities exploited

1 CVE Mallory has correlated with this family across public research and vendor advisories. Each row links to the full Mallory page for that vulnerability.

1 CVES
CVE-2020-1380Internet Explorer JScript use-after-free remote code executionExploited in the wild

The backdoor was used as the final payload of a multistage attack in early 2021, involving a watering-hole attack on a South Korean online newspaper, an Internet Explorer exploit, and another ScarCruft backdoor, named BLUELIGHT. | ScarCruft exploits CVE-2020-1380 to compromise victims.

via eset welivesecurity blogwelivesecurity.com
THREAT ACTORS

Groups observed using it

4 distinct threat actors attributed by public researchers. Open in Mallory to see the full evidence chain and overlapping campaigns.

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APT37

Stairwell found a new malware sample named “Goldbackdoor,” which was assessed as a successor of “Bluelight.”

via bleeping computerbleepingcomputer.com
vedalia

The first known usage was by the North Korea-linked Vedalia espionage group (aka APT37), which developed Bluelight, a second-stage payload that could communicate with several different cloud services for C&C purposes.

via symantec blogsecurity.com
APT42

BLUELIGHT can harvest cookies from Internet Explorer, Edge, Chrome, and Naver Whale browsers.

via mitre attackattack.mitre.org
Kimsuky

...and finally to BLUELIGHT and FOOTWINE for full surveillance.

via cyber security newscybersecuritynews.com
MITRE ATT&CK

Techniques & procedures

21 distinct techniques documented for this family, organized by ATT&CK tactic.

Initial Access

2 techniques
T1189Drive-by CompromiseEvidence1

The backdoor was used as the final payload of a multistage attack in early 2021, involving a watering-hole attack on a South Korean online newspaper, an Internet Explorer exploit, and another ScarCruft backdoor, named BLUELIGHT.

T1566PhishingEvidence1

The malware is distributed through a phishing attack... The phishing emails originated from the account of the former director of South Korea’s National Intelligence Service (NIS), who APT37 previously compromised.

Execution

2 techniques
T1059.007JavaScriptEvidence1

MITRE ATT&CK techniques... ScarCruft used malicious JavaScript for a watering-hole attack.

T1203Exploitation for Client ExecutionEvidence1

MITRE ATT&CK techniques... ScarCruft exploits CVE-2020-1380 to compromise victims.

Privilege Escalation

1 technique
T1055Process InjectionEvidence1

The Python loader includes a script and shellcode, launching a multi-step XOR-decryption, process creation, etc., eventually resulting in the execution of the Dolphin payload in a newly created memory process.

Stealth

3 techniques
T1027Obfuscated Files or InformationEvidence4

The content repeatedly describes adversaries using Base64, XOR, RC4, AES, hexadecimal encoding, string encryption, code flattening, custom crypters, and other obfuscation methods to hide payloads, strings, configuration data, URLs, and scripts.

T1055Process InjectionEvidence1

The Python loader includes a script and shellcode, launching a multi-step XOR-decryption, process creation, etc., eventually resulting in the execution of the Dolphin payload in a newly created memory process.

T1070.004File DeletionEvidence4

The content repeatedly describes threat actors and malware deleting files, tools, scripts, logs, droppers, staged data, and artifacts from compromised systems to cover tracks, remove evidence, or self-delete.

Credential Access

2 techniques
T1539Steal Web Session CookieEvidence2

"...used custom malware to steal login and cookie data from common browsers..."; "...extracts the web session cookie and sends it to the C2 server..."; "...stole Chrome browser cookies by copying the Chrome profile directories..."

T1555.003Credentials from Web BrowsersEvidence4

The content repeatedly describes threat actors and malware stealing usernames, passwords, cookies, session tokens, and other saved credentials from web browsers such as Chrome, Firefox, Internet Explorer, Edge, Opera, Safari, and Yandex.

Discovery

6 techniques
T1016System Network Configuration DiscoveryEvidence3

The content repeatedly describes malware and threat actors using commands and APIs such as ipconfig /all, ifconfig, arp -a, route print, nbtstat, netsh, GetAdaptersInfo, and GetIpNetTable to gather IP addresses, MAC addresses, DNS, DHCP, gateways, routing tables, ARP cache, proxy settings, domains, and network adapter/interface details.

T1033System Owner/User DiscoveryEvidence3

The content repeatedly describes malware and threat actors collecting usernames, identifying logged-in users, running whoami/query user/quser, checking whether the current user is an administrator, enumerating user sessions, and gathering account details from compromised hosts.

T1057Process DiscoveryEvidence2

The content repeatedly describes malware and threat actors obtaining lists of running processes, using utilities such as tasklist, ps, WMI, Get-Process, CreateToolhelp32Snapshot, EnumProcesses, and similar APIs/commands to enumerate active processes on victim systems.

T1082System Information DiscoveryEvidence4

The content repeatedly describes malware and threat actors collecting host details such as OS version, hostname, architecture, CPU, memory, BIOS, domain, language, and other configuration data; e.g., "APT41 uses multiple built-in commands such as systeminfo and net config Workstation to enumerate victim system basic configuration information."

T1083File and Directory DiscoveryEvidence3

The content repeatedly describes malware and threat actors listing files and directories, enumerating drives, searching for files by extension/name/path, retrieving file metadata, and browsing file systems (for example: "APT28 has used Forfiles to locate PDF, Excel, and Word documents during collection" and "cmd can be used to find files and directories with native functionality such as dir commands").

T1124System Time DiscoveryEvidence1

Multiple malware and threat groups are described as collecting/deriving local system time, date, timestamp, tick count, or time zone (e.g., "used time /t and net time \ip/hostname for system time discovery"; "collects the timestamp from the victim’s machine"; "can collect the time zone information from the system").

Collection

2 techniques
T1113Screen CaptureEvidence1

"Agent Tesla can capture screenshots of the victim’s desktop"; "AppleSeed can take screenshots on a compromised host"; "APT28 has used tools to take screenshots from victims"; "Cobalt Strike's Beacon payload is capable of capturing screenshots"; "PowerSploit's Get-TimedScreenshot Exfiltration module can take screenshots at regular intervals"; "Hydraq includes a component based on the code of VNC that can stream a live feed of the desktop"

T1560Archive Collected DataEvidence2

"AppleSeed has compressed collected data before exfiltration."; "APT28 used a publicly available tool to gather and compress multiple documents..."; "Aria-body has used ZIP to compress data..."; "Cadelspy...compress stolen data into a .cab file."; "Daserf hides collected data in password-protected .rar archives."; "FIN6 has compressed log files into a ZIP archive prior to staging and exfiltration."; "Lazarus Group has compressed exfiltrated data with RAR...archive specified directories in .zip format"; "XCSSET will compress entire ~/Desktop folders..."

Command and Control

3 techniques
T1071Application Layer ProtocolEvidence2

Several entries describe broader use of HTTP/HTTPS and related web mechanisms for C2, including "Crutch has conducted C2 communications with a Dropbox account using the HTTP API," "BLUELIGHT can use HTTP/S for C2 using the Microsoft Graph API," and "Small Sieve can contact actor-controlled C2 servers by using the Telegram API over HTTPS."

T1071.001Web ProtocolsEvidence4

The content repeatedly describes threat actors and malware using HTTP and HTTPS for command and control, such as: "Sandworm Team used BlackEnergy to communicate between compromised hosts and their command-and-control servers via HTTP post requests."

T1102Web ServiceEvidence4

The adversaries had communicated to both Dropbox and Pastebin. APT28 has used Google Drive for C2. APT37 leverages social networking sites and cloud platforms (AOL, Twitter, Yandex, Mediafire, pCloud, Dropbox, and Box) for C2.

Exfiltration

1 technique
T1041Exfiltration Over C2 ChannelEvidence2

ADVSTORESHELL exfiltrates data over the same channel used for C2... Agrius exfiltrated staged data using tools such as Putty and WinSCP, communicating with command and control servers... numerous malware and groups sent victim data, files, credentials, or host information over existing C2 channels.

INDICATORS OF COMPROMISE

IOCs tracked for this family

1 indicator attributed across vendor reports, sandbox runs, and researcher write-ups. Full values are available in Mallory.

View more in app
Hashes
1 tracked

File hashes (MD5, SHA-1, SHA-256) from samples and reports.

TypeValueLatest sighting
hash.sha256●●●●●●●●●●●●View more in app2 years ago
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IOC matching1

Match every observed IP, domain, and hash against your live telemetry.

Threat actor attribution4

Named campaigns wielding this family, with evidence pinned to each claim.

Exploited vulnerabilities1

CVEs this family uses for access and lateral movement.

Detection signatures

YARA, Sigma, Snort, and vendor rules, auto-deployed to your SIEM.

MITRE ATT&CK mapping21

Every documented technique, ranked by evidence weight.

Researcher chatter

Reddit, Mastodon, and CTI community discussion around this family.