Sub-technique of T1102 Web Service.View on attack.mitre.org
Adversaries may use an existing, legitimate external Web service to host information that points to additional command and control (C2) infrastructure. Adversaries may post content, known as a dead drop resolver, on Web services with embedded (and often obfuscated/encoded) domains or IP addresses. Once infected, victims will reach out to and be redirected by these resolvers.
Popular websites and social media acting as a mechanism for C2 may give a significant amount of cover due to the likelihood that hosts within a network are already communicating with them prior to a compromise. Using common services, such as those offered by Google or Twitter, makes it easier for adversaries to hide in expected noise. Web service providers commonly use SSL/TLS encryption, giving adversaries an added level of protection.
Use of a dead drop resolver may also protect back-end C2 infrastructure from discovery through malware binary analysis while also enabling operational resiliency (since this infrastructure may be dynamically changed).
Rules on DetectionCode tagged with T1102.001.
| Rule | Level | Log source |
|---|---|---|
| PwnDrp Access | critical | NULL / proxy |
| New Connection Initiated To Potential Dead Drop Resolver Domain | high | windows / network_connection |
| Raw Paste Service Access | high | NULL / proxy |
| Network Connection Initiated To AzureWebsites.NET By Non-Browser Process | medium | windows / network_connection |
| Used by | Procedure example |
|---|---|
| GroupAPT41 | APT41 used legitimate websites for C2 through dead drop resolvers (DDR), including GitHub, Pastebin, and Microsoft TechNet. |
| GroupBRONZE BUTLER | BRONZE BUTLER's MSGET downloader uses a dead drop resolver to access malicious payloads. |
| GroupKimsuky | Kimsuky has used TRANSLATEXT and a dead drop resolver to retrieve configurations and commands from a public blog site. |
| GroupPatchwork | Patchwork hides base64-encoded and encrypted C2 server locations in comments on legitimate websites. |
| GroupRocke | Rocke has used Pastebin to check the version of beaconing malware and redirect to another Pastebin hosting updated malware. |
| GroupRTM | RTM has used an RSS feed on Livejournal to update a list of encrypted C2 server names. |
| Used by | Procedure example |
|---|---|
| MalwareAstaroth | Astaroth can store C2 information on cloud hosting services such as AWS and CloudFlare and websites like YouTube and Facebook. |
| MalwareBADNEWS | BADNEWS collects C2 information via a dead drop resolver. |
| MalwareBLACKCOFFEE | BLACKCOFFEE uses Microsoft’s TechNet Web portal to obtain a dead drop resolver containing an encoded tag with the IP address of a command and control server. |
| MalwareCanisterWorm | CanisterWorm can periodically poll a decentralized Internet Computer Protocol (ICP) canister to retrieve a dynamic URL for payload delivery. |
| MalwareCharmPower | CharmPower can retrieve C2 domain information from actor-controlled S3 buckets. |
| MalwareGlassWorm | GlassWorm has leveraged blockchain-based C2 infrastructure to include Solana blockchain that contains additional C2 details within the memo field. GlassWorm has also leveraged Google Calendar to host encoded data. |
| MalwareGrandoreiro | Grandoreiro can obtain C2 information from Google Docs. |
| MalwareJavali | Javali can read C2 information from Google Documents and YouTube. |
| Used by | Procedure example |
|---|---|
| Campaign3CX Supply Chain Attack | During the 3CX Supply Chain Attack, AppleJeus leveraged a GitHub repository to host icon files containing the command and control URL. |
| CampaignC0017 | During C0017, APT41 used dead drop resolvers on two separate tech community forums for their KEYPLUG Windows-version backdoor; notably APT41 updated the community forum posts frequently with new dead drop resolvers during the campaign. |
Data from MITRE ATT&CK® (Enterprise). ATT&CK® is a registered trademark of The MITRE Corporation.
