{"description":"Trending threats, MITRE ATT\u0026CK coverage, and detection metadata — refreshed continuously.","feed_url":"https://feed.craftedsignal.io/products/slack/","home_page_url":"https://feed.craftedsignal.io/","items":[{"_cs_actors":[],"_cs_cves":[],"_cs_exploited":false,"_cs_products":["Elastic Defend","SentinelOne Cloud Funnel","Microsoft Teams","Google Chrome","Mozilla Firefox","Opera","Cisco WebEx","Discord","WhatsApp","Zoom","Brave Browser","Slack","thunderbird.exe"],"_cs_severities":["medium"],"_cs_tags":["defense-evasion","persistence","windows"],"_cs_type":"advisory","_cs_vendors":["Elastic","SentinelOne","Microsoft","Google","Mozilla","Opera","Cisco","Discord","WhatsApp","Zoom","Brave"],"content_html":"\u003cp\u003eThis detection rule focuses on identifying suspicious child processes of communication applications such as Slack, Cisco Webex, Microsoft Teams, Discord, WhatsApp, Zoom, and Thunderbird on Windows operating systems. Attackers may attempt to masquerade as legitimate processes or exploit vulnerabilities in these applications to execute malicious code. The rule monitors for the creation of child processes by these communication apps and checks if those child processes are unexpected, untrusted, or lack a valid code signature. This detection is crucial because successful exploitation can lead to unauthorized access, data exfiltration, or further compromise of the system. The rule has been actively maintained since August 2023, with updates as recent as May 2026, indicating its relevance and ongoing refinement to address emerging threats.\u003c/p\u003e\n\u003ch2 id=\"attack-chain\"\u003eAttack Chain\u003c/h2\u003e\n\u003col\u003e\n\u003cli\u003eUser launches a communication application (e.g., Slack, Teams, Webex).\u003c/li\u003e\n\u003cli\u003eThe communication application executes a vulnerable or compromised component.\u003c/li\u003e\n\u003cli\u003eThe compromised component spawns a child process (e.g., powershell.exe, cmd.exe).\u003c/li\u003e\n\u003cli\u003eThe child process executes a malicious command or script.\u003c/li\u003e\n\u003cli\u003eThe script attempts to download additional payloads from an external source.\u003c/li\u003e\n\u003cli\u003eThe payload executes, establishing persistence through registry modification or scheduled tasks.\u003c/li\u003e\n\u003cli\u003eThe attacker gains remote access to the system.\u003c/li\u003e\n\u003cli\u003eData exfiltration or lateral movement within the network occurs.\u003c/li\u003e\n\u003c/ol\u003e\n\u003ch2 id=\"impact\"\u003eImpact\u003c/h2\u003e\n\u003cp\u003eA successful attack can lead to the compromise of sensitive data, installation of malware, and potential lateral movement within the organization\u0026rsquo;s network. By exploiting communication applications, attackers can gain access to internal communications, confidential documents, and user credentials. The number of affected users and the extent of the damage depend on the compromised application and the attacker\u0026rsquo;s objectives. If successful, this attack may lead to significant financial loss, reputational damage, and disruption of business operations.\u003c/p\u003e\n\u003ch2 id=\"recommendation\"\u003eRecommendation\u003c/h2\u003e\n\u003cul\u003e\n\u003cli\u003eDeploy the Sigma rule \u003ccode\u003eSuspicious Communication App Child Process\u003c/code\u003e to your SIEM to detect anomalous child processes spawned by communication applications and tune for your environment.\u003c/li\u003e\n\u003cli\u003eEnable process creation logging with command line arguments in Windows to ensure that the Sigma rule has the necessary data to function correctly (logsource: \u003ccode\u003eprocess_creation\u003c/code\u003e, product: \u003ccode\u003ewindows\u003c/code\u003e).\u003c/li\u003e\n\u003cli\u003eInvestigate any alerts generated by the rule and review the command line arguments of the spawned processes to identify potential malicious activity.\u003c/li\u003e\n\u003cli\u003eImplement application whitelisting to restrict the execution of unauthorized applications and reduce the attack surface.\u003c/li\u003e\n\u003cli\u003eEnsure that all communication applications are updated to the latest versions to patch known vulnerabilities and reduce the risk of exploitation.\u003c/li\u003e\n\u003cli\u003eExamine the network activity of the affected system to identify any suspicious outbound connections that may indicate data exfiltration or communication with a command and control server, referencing the setup guide.\u003c/li\u003e\n\u003c/ul\u003e\n","date_modified":"2024-01-31T12:00:00Z","date_published":"2024-01-31T12:00:00Z","id":"/briefs/2024-01-suspicious-comm-app-child-process/","summary":"The detection rule identifies suspicious child processes spawned from communication applications on Windows systems, potentially indicating masquerading or exploitation of vulnerabilities within these applications.","title":"Suspicious Child Processes from Communication Applications","url":"https://feed.craftedsignal.io/briefs/2024-01-suspicious-comm-app-child-process/"},{"_cs_actors":[],"_cs_cves":[],"_cs_exploited":false,"_cs_products":["OneDrive","Chrome","Brave","Opera","Discord","Slack","Microsoft 365","SharePoint"],"_cs_severities":["medium"],"_cs_tags":["command-and-control","windows","threat-detection"],"_cs_type":"advisory","_cs_vendors":["Microsoft","Google","Brave Software","Opera","Discord","Slack"],"content_html":"\u003cp\u003eAdversaries may implement command and control (C2) communications that use common web services to hide their activity. This attack technique is typically targeted at an organization and uses web services common to the victim network, which allows the adversary to blend into legitimate traffic activity. These popular services are typically targeted since they have most likely been used before compromise, which helps malicious traffic blend in. This detection focuses on identifying connections from Windows hosts to a predefined list of commonly abused web services from processes running outside of typical program installation directories, indicating a potential C2 channel leveraging legitimate services. The rule aims to detect this behavior by monitoring network connections and DNS requests originating from unusual locations.\u003c/p\u003e\n\u003ch2 id=\"attack-chain\"\u003eAttack Chain\u003c/h2\u003e\n\u003col\u003e\n\u003cli\u003eInitial access is achieved via an unknown method (e.g., phishing, exploit).\u003c/li\u003e\n\u003cli\u003eMalware is installed on the victim\u0026rsquo;s system, likely outside typical program directories.\u003c/li\u003e\n\u003cli\u003eThe malware establishes a DNS connection to a commonly abused web service (e.g., pastebin.com, raw.githubusercontent.com) to obscure C2 traffic.\u003c/li\u003e\n\u003cli\u003eThe malware sends encrypted or encoded commands to the web service.\u003c/li\u003e\n\u003cli\u003eThe web service acts as an intermediary, relaying the commands to the attacker\u0026rsquo;s C2 server.\u003c/li\u003e\n\u003cli\u003eThe C2 server responds with instructions, which are then relayed back to the compromised host through the same web service.\u003c/li\u003e\n\u003cli\u003eThe malware executes the received commands, potentially leading to data exfiltration, lateral movement, or other malicious activities.\u003c/li\u003e\n\u003cli\u003eThe attacker maintains persistent access and control over the compromised system using the web service as a hidden C2 channel.\u003c/li\u003e\n\u003c/ol\u003e\n\u003ch2 id=\"impact\"\u003eImpact\u003c/h2\u003e\n\u003cp\u003eSuccessful exploitation can lead to data theft, system compromise, and further propagation within the network. Since commonly used web services are utilized, the malicious activity can blend in with legitimate network traffic, making it difficult to detect. The impact can range from minor data breaches to complete network compromise, depending on the attacker\u0026rsquo;s objectives and the level of access gained.\u003c/p\u003e\n\u003ch2 id=\"recommendation\"\u003eRecommendation\u003c/h2\u003e\n\u003cul\u003e\n\u003cli\u003eDeploy the Sigma rule \u003ccode\u003eDetect Commonly Abused Web Services via DNS\u003c/code\u003e to your SIEM to identify suspicious DNS queries to known C2 web services originating from anomalous processes.\u003c/li\u003e\n\u003cli\u003eEnable DNS query logging on Windows endpoints to provide the data source required for the Sigma rule.\u003c/li\u003e\n\u003cli\u003eReview network connection logs for processes outside standard installation directories communicating with domains listed in the \u003ccode\u003equery\u003c/code\u003e section of the Sigma rule to identify potential C2 activity.\u003c/li\u003e\n\u003cli\u003eImplement network segmentation to limit the potential impact of compromised hosts.\u003c/li\u003e\n\u003c/ul\u003e\n","date_modified":"2024-01-04T12:00:00Z","date_published":"2024-01-04T12:00:00Z","id":"/briefs/2024-01-04-c2-web-services/","summary":"This rule detects command and control activity using common web services by identifying Windows hosts making DNS requests to a list of commonly abused web services from processes outside of known program locations, potentially indicating adversaries attempting to blend malicious traffic with legitimate network activity.","title":"Detection of Command and Control Activity via Commonly Abused Web Services","url":"https://feed.craftedsignal.io/briefs/2024-01-04-c2-web-services/"},{"_cs_actors":[],"_cs_cves":[],"_cs_exploited":false,"_cs_products":["Firefox","Thunderbird","VMware Horizon View Client","Dropbox Client","Google Earth Pro","CrashPlan","Pale Moon","Waterfox","Cyberfox","Slack"],"_cs_severities":["high"],"_cs_tags":["defense-evasion","anomaly","windows"],"_cs_type":"advisory","_cs_vendors":["Mozilla","VMware","Dropbox","Google","Code42","Slack"],"content_html":"\u003cp\u003eThis brief focuses on detecting anomalous loading of Mozilla NSS (Network Security Services) and Mozglue libraries (specifically \u003ccode\u003emozglue.dll\u003c/code\u003e and \u003ccode\u003enss3.dll\u003c/code\u003e) by processes other than known Mozilla applications like Firefox and Thunderbird. The technique leverages Windows Sysmon Event ID 7 (ImageLoaded) to identify such instances. This activity is flagged as suspicious because legitimate software rarely loads these libraries outside of the intended Mozilla ecosystem. Attackers may attempt to load these libraries into other processes to perform malicious actions such as code injection, data exfiltration, or credential theft, while masquerading as legitimate software. This detection is crucial for identifying potentially compromised systems and preventing further damage.\u003c/p\u003e\n\u003ch2 id=\"attack-chain\"\u003eAttack Chain\u003c/h2\u003e\n\u003col\u003e\n\u003cli\u003e\u003cstrong\u003eInitial Access:\u003c/strong\u003e An attacker gains initial access to the system, possibly through phishing, exploiting a vulnerability, or using stolen credentials.\u003c/li\u003e\n\u003cli\u003e\u003cstrong\u003ePersistence:\u003c/strong\u003e The attacker establishes persistence on the system, ensuring continued access even after a reboot. This may involve creating scheduled tasks or modifying registry keys.\u003c/li\u003e\n\u003cli\u003e\u003cstrong\u003ePrivilege Escalation:\u003c/strong\u003e The attacker elevates privileges to gain higher-level access to the system. This can be achieved through exploiting kernel vulnerabilities or misconfigured services.\u003c/li\u003e\n\u003cli\u003e\u003cstrong\u003eMalware Installation:\u003c/strong\u003e The attacker deploys malware or malicious tools onto the compromised system. This may involve downloading executables or scripts from a remote server.\u003c/li\u003e\n\u003cli\u003e\u003cstrong\u003eCode Injection:\u003c/strong\u003e The attacker injects malicious code into a legitimate process. This is often done to evade detection and execute malicious commands in a trusted context. In this scenario, the injected code might leverage Mozilla NSS/Mozglue libraries.\u003c/li\u003e\n\u003cli\u003e\u003cstrong\u003eCredential Theft:\u003c/strong\u003e The injected code attempts to steal credentials stored on the system. This may involve accessing LSASS memory or extracting credentials from web browsers.\u003c/li\u003e\n\u003cli\u003e\u003cstrong\u003eData Exfiltration:\u003c/strong\u003e The attacker exfiltrates sensitive data from the compromised system. This may involve compressing data and transferring it to a remote server using protocols like HTTP or FTP.\u003c/li\u003e\n\u003cli\u003e\u003cstrong\u003eLateral Movement/Impact:\u003c/strong\u003e Using stolen credentials or the compromised system as a pivot, the attacker moves laterally within the network to compromise additional systems, or achieves their ultimate objective, such as ransomware deployment or intellectual property theft.\u003c/li\u003e\n\u003c/ol\u003e\n\u003ch2 id=\"impact\"\u003eImpact\u003c/h2\u003e\n\u003cp\u003eSuccessful exploitation and anomalous loading of Mozilla libraries can lead to significant damage, including data breaches, financial loss, and reputational damage. Stolen credentials can be used to access sensitive systems and data, while injected code can disrupt critical business processes. The scope can range from individual workstations to entire networks, depending on the attacker\u0026rsquo;s objectives and level of access. The detection helps prevent credential theft, data exfiltration, and lateral movement.\u003c/p\u003e\n\u003ch2 id=\"recommendation\"\u003eRecommendation\u003c/h2\u003e\n\u003cul\u003e\n\u003cli\u003eEnable Sysmon Event ID 7 (ImageLoaded) logging on all Windows endpoints to ensure visibility into loaded modules (reference: \u003ccode\u003edata_source\u003c/code\u003e).\u003c/li\u003e\n\u003cli\u003eDeploy the Sigma rule \u003ccode\u003eUnusual Mozilla NSS/Mozglue Module Load by Non-Mozilla Process\u003c/code\u003e to your SIEM and tune the process exceptions for your environment (reference: \u003ccode\u003erules\u003c/code\u003e).\u003c/li\u003e\n\u003cli\u003eInvestigate any instances where Mozilla NSS/Mozglue libraries are loaded by processes not explicitly allowed in the exception list to determine if malicious activity is occurring (reference: \u003ccode\u003esearch\u003c/code\u003e).\u003c/li\u003e\n\u003cli\u003eCorrelate detections of unusual Mozilla library loading with other suspicious activity, such as network connections to known malicious domains or the execution of unusual processes, to identify potential compromises (reference: \u003ccode\u003etags\u003c/code\u003e).\u003c/li\u003e\n\u003cli\u003eReview and update the list of legitimate applications that may load Mozilla NSS/Mozglue libraries in your environment to reduce false positives (reference: \u003ccode\u003eknown_false_positives\u003c/code\u003e).\u003c/li\u003e\n\u003c/ul\u003e\n","date_modified":"2024-01-03T14:30:00Z","date_published":"2024-01-03T14:30:00Z","id":"/briefs/2024-01-03-unusual-mozglue-load/","summary":"Detection of processes loading Mozilla NSS/Mozglue libraries (mozglue.dll, nss3.dll) outside of known Mozilla applications, potentially indicating malware or unauthorized activity.","title":"Unusual Process Loading Mozilla NSS/Mozglue Module","url":"https://feed.craftedsignal.io/briefs/2024-01-03-unusual-mozglue-load/"},{"_cs_actors":[],"_cs_cves":[],"_cs_exploited":false,"_cs_products":["Slack","WebEx","Teams","Discord","Rocket.Chat","Mattermost","WhatsApp","Zoom","Outlook","Thunderbird"],"_cs_severities":["medium"],"_cs_tags":["defense-evasion","masquerading","windows"],"_cs_type":"advisory","_cs_vendors":["Slack Technologies","Cisco","Microsoft","Discord","Rocket.Chat Technologies","Mattermost","WhatsApp","Zoom Video Communications","Mozilla"],"content_html":"\u003cp\u003eAttackers may attempt to evade defenses by masquerading malicious processes as legitimate communication applications. This involves using names and icons that resemble trusted applications like Slack, WebEx, Teams, Discord, RocketChat, Mattermost, WhatsApp, Zoom, Outlook and Thunderbird to trick users and bypass security measures. This technique can be used to conceal malicious activity, bypass allowlists, or trick users into executing malware. The detection rule identifies suspicious instances by checking for unsigned or improperly signed processes, ensuring they match known trusted signatures, which helps in flagging potential threats that mimic trusted communication tools.\u003c/p\u003e\n\u003ch2 id=\"attack-chain\"\u003eAttack Chain\u003c/h2\u003e\n\u003col\u003e\n\u003cli\u003eAn attacker gains initial access to a Windows system through various means such as phishing or exploiting a vulnerability.\u003c/li\u003e\n\u003cli\u003eThe attacker deploys a malicious executable onto the compromised system.\u003c/li\u003e\n\u003cli\u003eThe attacker renames the malicious executable to resemble a legitimate communication application, such as \u0026ldquo;slack.exe\u0026rdquo; or \u0026ldquo;Teams.exe\u0026rdquo;.\u003c/li\u003e\n\u003cli\u003eThe attacker modifies or removes the code signature of the malicious executable to avoid detection based on trusted publishers.\u003c/li\u003e\n\u003cli\u003eThe attacker executes the renamed and potentially unsigned malicious executable.\u003c/li\u003e\n\u003cli\u003eThe masqueraded process performs malicious actions, such as establishing a reverse shell or downloading additional payloads.\u003c/li\u003e\n\u003cli\u003eThe attacker uses the compromised system to move laterally within the network, escalating privileges and compromising additional systems.\u003c/li\u003e\n\u003cli\u003eThe final objective is to exfiltrate sensitive data or deploy ransomware.\u003c/li\u003e\n\u003c/ol\u003e\n\u003ch2 id=\"impact\"\u003eImpact\u003c/h2\u003e\n\u003cp\u003eSuccessful masquerading attacks can lead to significant security breaches, including data theft, system compromise, and financial loss. By disguising malicious processes as legitimate communication apps, attackers can bypass security controls and operate undetected for extended periods. This can result in widespread damage and disruption, as well as reputational damage for the targeted organization. The impact can range from a few compromised systems to a complete network takeover, depending on the attacker\u0026rsquo;s objectives and the effectiveness of the masquerading technique.\u003c/p\u003e\n\u003ch2 id=\"recommendation\"\u003eRecommendation\u003c/h2\u003e\n\u003cul\u003e\n\u003cli\u003eDeploy the Sigma rule \u0026ldquo;Potential Masquerading as Communication Apps - Generic\u0026rdquo; to your SIEM and tune for your environment to detect unsigned or improperly signed communication applications.\u003c/li\u003e\n\u003cli\u003eDeploy the Sigma rule \u0026ldquo;Potential Masquerading as Communication Apps - Specific\u0026rdquo; to your SIEM and tune for your environment to detect unsigned or improperly signed instances of specific communication applications.\u003c/li\u003e\n\u003cli\u003eEnable process creation logging on Windows systems to capture the necessary events for the Sigma rules.\u003c/li\u003e\n\u003cli\u003eReview and validate the code signatures of all communication apps on your systems to ensure they are properly signed by trusted entities.\u003c/li\u003e\n\u003cli\u003eImplement application control policies to restrict the execution of unsigned or untrusted executables.\u003c/li\u003e\n\u003c/ul\u003e\n","date_modified":"2024-01-03T12:00:00Z","date_published":"2024-01-03T12:00:00Z","id":"/briefs/2024-01-masquerading-communication-apps/","summary":"Attackers may attempt to evade defenses by masquerading malicious processes as legitimate communication applications such as Slack, WebEx, Teams, Discord, RocketChat, Mattermost, WhatsApp, Zoom, Outlook and Thunderbird.","title":"Potential Masquerading as Communication Apps","url":"https://feed.craftedsignal.io/briefs/2024-01-masquerading-communication-apps/"},{"_cs_actors":[],"_cs_cves":[],"_cs_exploited":false,"_cs_products":["Elastic Defend","Slack","WebEx","Teams","Discord","WhatsApp","Zoom","Outlook","Thunderbird","Grammarly","Dropbox","Tableau","Google Drive","MSOffice","Okta","OneDrive","Chrome","Firefox","Edge","Brave","GoogleCloud Related Tools","Github Related Tools","Notion"],"_cs_severities":["medium"],"_cs_tags":["masquerading","defense-evasion","initial-access","malware","windows"],"_cs_type":"advisory","_cs_vendors":["Elastic","Slack","Cisco","Microsoft","Discord","Zoom","Mozilla","Grammarly","Dropbox","Tableau","Google","Okta","Brave","GitHub","Notion"],"content_html":"\u003cp\u003eAttackers often attempt to trick users into downloading and executing malicious executables by disguising them as legitimate business applications. This tactic is used to bypass security measures and gain initial access to a system. These malicious executables, often distributed via malicious ads, forum posts, and tutorials, mimic the names of commonly used applications such as Slack, WebEx, Teams, Discord, and Zoom. The executables are typically unsigned or signed with invalid certificates to further evade detection. This allows the attacker to execute arbitrary code on the victim\u0026rsquo;s machine, potentially leading to further compromise. This campaign aims to target end-users who are less security-aware, and this makes social engineering attacks like this very effective.\u003c/p\u003e\n\u003ch2 id=\"attack-chain\"\u003eAttack Chain\u003c/h2\u003e\n\u003col\u003e\n\u003cli\u003eThe user visits a compromised website or clicks on a malicious advertisement.\u003c/li\u003e\n\u003cli\u003eThe user is prompted to download an installer file masquerading as a legitimate business application (e.g., Slack, Zoom, Teams) from a download directory.\u003c/li\u003e\n\u003cli\u003eThe downloaded executable is placed in the user\u0026rsquo;s Downloads folder (e.g., C:\\Users*\\Downloads*).\u003c/li\u003e\n\u003cli\u003eThe user executes the downloaded file.\u003c/li\u003e\n\u003cli\u003eThe executable, lacking a valid code signature, begins execution.\u003c/li\u003e\n\u003cli\u003eThe malicious installer may drop and execute additional malware components.\u003c/li\u003e\n\u003cli\u003eThe malware establishes persistence, potentially using techniques such as registry key modification.\u003c/li\u003e\n\u003cli\u003eThe malware performs malicious activities, such as data exfiltration or lateral movement.\u003c/li\u003e\n\u003c/ol\u003e\n\u003ch2 id=\"impact\"\u003eImpact\u003c/h2\u003e\n\u003cp\u003eSuccessful execution of a masqueraded business application installer can lead to a complete system compromise. The attacker gains initial access and can deploy various malware payloads, including ransomware, keyloggers, and data stealers. This can result in data breaches, financial loss, and reputational damage. Although the specific number of victims and sectors targeted are not detailed, the widespread use of the applications being spoofed (Slack, Zoom, etc.) suggests a broad potential impact.\u003c/p\u003e\n\u003ch2 id=\"recommendation\"\u003eRecommendation\u003c/h2\u003e\n\u003cul\u003e\n\u003cli\u003eImplement the Sigma rule \u003ccode\u003ePotential Masquerading as Business App Installer\u003c/code\u003e to detect unsigned executables resembling legitimate business applications in download directories.\u003c/li\u003e\n\u003cli\u003eEnable process creation logging to capture the execution of unsigned executables.\u003c/li\u003e\n\u003cli\u003eEducate users on the risks of downloading and executing files from untrusted sources.\u003c/li\u003e\n\u003cli\u003eImplement application whitelisting to restrict the execution of unauthorized applications.\u003c/li\u003e\n\u003cli\u003eRegularly update endpoint detection and response (EDR) tools to detect and prevent the execution of known malware.\u003c/li\u003e\n\u003cli\u003eMonitor process execution events for processes originating from the Downloads folder that lack valid code signatures.\u003c/li\u003e\n\u003c/ul\u003e\n","date_modified":"2024-01-02T12:00:00Z","date_published":"2024-01-02T12:00:00Z","id":"/briefs/2024-01-masquerading-business-apps/","summary":"Attackers masquerade malicious executables as legitimate business application installers to trick users into downloading and executing malware, leveraging defense evasion and initial access techniques.","title":"Masquerading Business Application Installers","url":"https://feed.craftedsignal.io/briefs/2024-01-masquerading-business-apps/"}],"language":"en","title":"CraftedSignal Threat Feed — Slack","version":"https://jsonfeed.org/version/1.1"}