{"description":"Trending threats, MITRE ATT\u0026CK coverage, and detection metadata. Fed continuously.","feed_url":"https://feed.craftedsignal.io/products/bitdefender-submission-wizard/feed.json","home_page_url":"https://feed.craftedsignal.io/","items":[{"_cs_actors":["Lotus Blossom"],"_cs_cpes":[],"_cs_cves":[],"_cs_exploited":false,"_cs_has_poc":false,"_cs_poc_references":[],"_cs_products":["Windows","Bitdefender Submission Wizard"],"_cs_severities":["high"],"_cs_tags":["rundll32","dll-sideloading","lotus-blossom","chrysalis-backdoor"],"_cs_type":"threat","_cs_vendors":["Microsoft","Bitdefender"],"content_html":"\u003cp\u003eThis threat brief focuses on the abuse of \u003ccode\u003erundll32.exe\u003c/code\u003e to execute malicious DLLs, specifically \u003ccode\u003elog.dll\u003c/code\u003e, a technique associated with the Lotus Blossom group's Chrysalis backdoor. The attacker places a rogue \u003ccode\u003elog.dll\u003c/code\u003e in a location such as \u003ccode\u003e%AppData%\\Bluetooth\u003c/code\u003e and leverages \u003ccode\u003erundll32.exe\u003c/code\u003e to invoke a specific function within the DLL (e.g., \u003ccode\u003eLogInit\u003c/code\u003e). This execution decrypts and runs shellcode. While some legitimate applications like the Bitdefender Submission Wizard also use \u003ccode\u003elog.dll\u003c/code\u003e, they are susceptible to DLL sideloading attacks, making this detection crucial for identifying malicious activity that bypasses traditional defenses. This campaign was first reported in 2026 and continues to be a relevant threat.\u003c/p\u003e\n\u003ch2 id=\"attack-chain\"\u003eAttack Chain\u003c/h2\u003e\n\u003col\u003e\n\u003cli\u003eThe attacker gains initial access, often through social engineering or exploiting software vulnerabilities (not specified in source).\u003c/li\u003e\n\u003cli\u003eA malicious \u003ccode\u003elog.dll\u003c/code\u003e is placed in a writable directory, such as \u003ccode\u003e%AppData%\\Bluetooth\u003c/code\u003e, mimicking a legitimate DLL location.\u003c/li\u003e\n\u003cli\u003eThe attacker uses \u003ccode\u003erundll32.exe\u003c/code\u003e to execute the malicious \u003ccode\u003elog.dll\u003c/code\u003e with a specific function call (e.g., \u003ccode\u003erundll32.exe log.dll,LogInit\u003c/code\u003e).\u003c/li\u003e\n\u003cli\u003e\u003ccode\u003eRundll32.exe\u003c/code\u003e loads and executes the \u003ccode\u003elog.dll\u003c/code\u003e.\u003c/li\u003e\n\u003cli\u003eThe \u003ccode\u003eLogInit\u003c/code\u003e function in \u003ccode\u003elog.dll\u003c/code\u003e decrypts embedded shellcode.\u003c/li\u003e\n\u003cli\u003eThe shellcode is injected into a legitimate process or executed directly, establishing persistence or escalating privileges.\u003c/li\u003e\n\u003cli\u003eThe injected shellcode connects to a command-and-control (C2) server to download additional payloads or receive instructions.\u003c/li\u003e\n\u003cli\u003eThe attacker performs actions on the compromised system, such as data exfiltration, lateral movement, or installing additional malware.\u003c/li\u003e\n\u003c/ol\u003e\n\u003ch2 id=\"impact\"\u003eImpact\u003c/h2\u003e\n\u003cp\u003eSuccessful exploitation can lead to complete system compromise, data theft, and the installation of persistent backdoors. The Lotus Blossom group has been known to target organizations across various sectors. The ability to bypass traditional security measures through DLL sideloading makes this a high-impact threat. Even legitimate software can become an attack vector.\u003c/p\u003e\n\u003ch2 id=\"recommendation\"\u003eRecommendation\u003c/h2\u003e\n\u003cul\u003e\n\u003cli\u003eDeploy the Sigma rule \u003ccode\u003eRundll32 Execution with Log.DLL\u003c/code\u003e to detect malicious \u003ccode\u003erundll32.exe\u003c/code\u003e executions using \u003ccode\u003elog.dll\u003c/code\u003e (logsource: process_creation).\u003c/li\u003e\n\u003cli\u003eInvestigate any \u003ccode\u003erundll32.exe\u003c/code\u003e process executions with \u003ccode\u003elog.dll\u003c/code\u003e as a command-line argument, especially when originating from unusual paths (Sigma rule \u003ccode\u003eRundll32 Execution with Log.DLL\u003c/code\u003e).\u003c/li\u003e\n\u003cli\u003eMonitor for suspicious file creations or modifications in \u003ccode\u003e%AppData%\\Bluetooth\u003c/code\u003e or other common DLL sideloading locations (logsource: file_event).\u003c/li\u003e\n\u003cli\u003eImplement application control policies to restrict the execution of \u003ccode\u003erundll32.exe\u003c/code\u003e from untrusted locations.\u003c/li\u003e\n\u003cli\u003eAudit systems for DLL sideloading vulnerabilities in legitimate applications.\u003c/li\u003e\n\u003c/ul\u003e\n","date_modified":"2024-01-03T12:00:00Z","date_published":"2024-01-03T12:00:00Z","id":"https://feed.craftedsignal.io/briefs/2024-01-rundll32-logdll/","summary":"Detects the execution of rundll32 with 'log.dll' as a command-line argument, indicative of Lotus Blossom Chrysalis backdoor activity and DLL sideloading attempts.","title":"Rundll32 Execution with Log.DLL","url":"https://feed.craftedsignal.io/briefs/2024-01-rundll32-logdll/"},{"_cs_actors":["Lotus Blossom"],"_cs_cpes":[],"_cs_cves":[],"_cs_exploited":false,"_cs_has_poc":false,"_cs_poc_references":[],"_cs_products":["Bitdefender Submission Wizard"],"_cs_severities":["high"],"_cs_tags":["dll-sideloading","persistence","privilege-escalation","lotus-blossom","sysmon"],"_cs_type":"threat","_cs_vendors":["Bitdefender"],"content_html":"\u003cp\u003eThis threat brief addresses the potential DLL side-loading attack targeting Bitdefender Submission Wizard (BDSubmit.exe, bdsw.exe, or renamed BluetoothService.exe). The attack involves a malicious actor placing a rogue log.dll in a directory where the legitimate Bitdefender executable will load it, thus executing attacker-controlled code. This technique is associated with the Lotus Blossom group (G0065). The observed activity relies on exploiting the DLL search order to execute arbitrary code. Defenders should monitor for instances of BDSubmit.exe, bdsw.exe, or BluetoothService.exe loading log.dll from unexpected paths outside of standard installation directories such as \u0026quot;Program Files\u0026quot; or \u0026quot;Windows\\System32\u0026quot;.\u003c/p\u003e\n\u003ch2 id=\"attack-chain\"\u003eAttack Chain\u003c/h2\u003e\n\u003col\u003e\n\u003cli\u003eThe attacker gains initial access to the system (method unspecified in source).\u003c/li\u003e\n\u003cli\u003eThe attacker identifies a vulnerable executable, such as BDSubmit.exe or bdsw.exe.\u003c/li\u003e\n\u003cli\u003eThe attacker crafts a malicious log.dll.\u003c/li\u003e\n\u003cli\u003eThe attacker places the malicious log.dll in the same directory as the Bitdefender executable, or in a directory that takes precedence in the DLL search order.\u003c/li\u003e\n\u003cli\u003eA user executes the legitimate Bitdefender Submission Wizard executable (BDSubmit.exe, bdsw.exe, or renamed BluetoothService.exe).\u003c/li\u003e\n\u003cli\u003eThe legitimate application attempts to load log.dll. Due to DLL side-loading, the malicious log.dll is loaded instead of the legitimate one.\u003c/li\u003e\n\u003cli\u003eThe malicious log.dll executes attacker-controlled code within the context of the Bitdefender Submission Wizard process.\u003c/li\u003e\n\u003cli\u003eThe attacker achieves code execution for persistence or privilege escalation.\u003c/li\u003e\n\u003c/ol\u003e\n\u003ch2 id=\"impact\"\u003eImpact\u003c/h2\u003e\n\u003cp\u003eSuccessful exploitation through DLL side-loading allows attackers to execute arbitrary code within a trusted process. This can lead to privilege escalation, persistence, and potentially complete system compromise. Specific impacts include unauthorized access to sensitive data, installation of malware, and lateral movement within the network. The Lotus Blossom group has been known to use similar techniques to deploy backdoors.\u003c/p\u003e\n\u003ch2 id=\"recommendation\"\u003eRecommendation\u003c/h2\u003e\n\u003cul\u003e\n\u003cli\u003eEnable Sysmon ImageLoad events (EventCode 7) to monitor DLL loading activity and ensure the Splunk Add-on for Sysmon is configured to parse them as described in the \u0026quot;how_to_implement\u0026quot; section.\u003c/li\u003e\n\u003cli\u003eDeploy the Sigma rule \u0026quot;Bitdefender Submission Wizard DLL Sideloading\u0026quot; to detect instances where log.dll is loaded from a non-standard path, and tune for your environment.\u003c/li\u003e\n\u003cli\u003eInvestigate any alerts generated by the provided detection rule, focusing on the \u0026quot;dest\u0026quot; and \u0026quot;User\u0026quot; fields as described in the \u0026quot;drilldown_searches\u0026quot; section.\u003c/li\u003e\n\u003cli\u003eMonitor for the execution of BDSubmit.exe, bdsw.exe, or BluetoothService.exe from unusual locations or with unusual command-line arguments.\u003c/li\u003e\n\u003cli\u003eReview and harden DLL search order configurations to prevent side-loading attacks (T1574.002).\u003c/li\u003e\n\u003c/ul\u003e\n","date_modified":"2024-01-02T10:00:00Z","date_published":"2024-01-02T10:00:00Z","id":"https://feed.craftedsignal.io/briefs/2024-01-02-bitdefender-dll-sideloading/","summary":"Detection of potential DLL side-loading of Bitdefender Submission Wizard (BDSubmit.exe, bdsw.exe, or renamed BluetoothService.exe) via loading a malicious log.dll from a non-standard path.","title":"Bitdefender Submission Wizard DLL Sideloading","url":"https://feed.craftedsignal.io/briefs/2024-01-02-bitdefender-dll-sideloading/"}],"language":"en","title":"CraftedSignal Threat Feed - Bitdefender Submission Wizard","version":"https://jsonfeed.org/version/1.1"}