{"description":"Trending threats, MITRE ATT\u0026CK coverage, and detection metadata. Fed continuously.","feed_url":"https://feed.craftedsignal.io/products/adobe-acrobat/feed.json","home_page_url":"https://feed.craftedsignal.io/","items":[{"_cs_actors":[],"_cs_cpes":[],"_cs_cves":[],"_cs_exploited":false,"_cs_has_poc":false,"_cs_poc_references":[],"_cs_products":["Adobe Acrobat Reader","Adobe Acrobat","Foxit PDF Reader","Foxit PDF Editor"],"_cs_severities":["medium"],"_cs_tags":["exploitation","pdf","initial-access"],"_cs_type":"advisory","_cs_vendors":["Adobe","Foxit"],"content_html":"\u003cp\u003eAttackers frequently target PDF reader applications due to their widespread use and complex codebase, providing multiple avenues for exploitation. These exploits can range from memory corruption vulnerabilities to logic flaws that allow arbitrary code execution. Social engineering is also a common tactic, where users are tricked into opening malicious PDF files that trigger the execution of embedded scripts or commands. The spawned processes often include system utilities used for reconnaissance or persistence. This technique is used for initial access, defense evasion, and discovery within the targeted environment. The detection rule provided by Elastic identifies suspicious child processes of PDF reader applications.\u003c/p\u003e\n\u003ch2 id=\"attack-chain\"\u003eAttack Chain\u003c/h2\u003e\n\u003col\u003e\n\u003cli\u003eA user receives a spearphishing email with a malicious PDF attachment (T1566.001).\u003c/li\u003e\n\u003cli\u003eThe user opens the PDF file using a vulnerable PDF reader application (e.g., Acrobat Reader, Foxit Reader).\u003c/li\u003e\n\u003cli\u003eThe PDF file exploits a vulnerability in the PDF reader, triggering the execution of embedded JavaScript or shell commands (T1203, T1204.002).\u003c/li\u003e\n\u003cli\u003eThe exploited PDF reader process (AcroRd32.exe, Acrobat.exe, FoxitPhantomPDF.exe, FoxitReader.exe) spawns a suspicious child process such as \u003ccode\u003ecmd.exe\u003c/code\u003e or \u003ccode\u003epowershell.exe\u003c/code\u003e (T1059.001).\u003c/li\u003e\n\u003cli\u003eThe spawned process executes discovery commands (e.g., \u003ccode\u003ewhoami.exe\u003c/code\u003e, \u003ccode\u003esysteminfo.exe\u003c/code\u003e, \u003ccode\u003enet.exe\u003c/code\u003e, \u003ccode\u003eipconfig.exe\u003c/code\u003e) to gather information about the system and network (T1082, T1016, T1033, T1057).\u003c/li\u003e\n\u003cli\u003eThe attacker may use system binary proxy execution (T1218) techniques by invoking utilities such as \u003ccode\u003emshta.exe\u003c/code\u003e, \u003ccode\u003eregsvr32.exe\u003c/code\u003e, or \u003ccode\u003einstallutil.exe\u003c/code\u003e to execute malicious code.\u003c/li\u003e\n\u003cli\u003eThe attacker establishes persistence on the system, potentially using scheduled tasks (\u003ccode\u003eschtasks.exe\u003c/code\u003e) or registry modifications (\u003ccode\u003ereg.exe\u003c/code\u003e).\u003c/li\u003e\n\u003cli\u003eThe attacker moves laterally within the network, escalating privileges, and exfiltrating sensitive data, or deploying ransomware.\u003c/li\u003e\n\u003c/ol\u003e\n\u003ch2 id=\"impact\"\u003eImpact\u003c/h2\u003e\n\u003cp\u003eCompromised systems can lead to data theft, system disruption, and further propagation of the attack within the network. Successful exploitation of PDF reader vulnerabilities can provide attackers with initial access to the target environment, potentially impacting hundreds or thousands of machines across an organization. The impact can range from minor data breaches to full-scale ransomware deployment, depending on the attacker's objectives.\u003c/p\u003e\n\u003ch2 id=\"recommendation\"\u003eRecommendation\u003c/h2\u003e\n\u003cul\u003e\n\u003cli\u003eDeploy the Sigma rule \u0026quot;Suspicious PDF Reader Child Process\u0026quot; to your SIEM to detect suspicious child processes spawned by PDF readers.\u003c/li\u003e\n\u003cli\u003eEnable process creation logging, specifically monitoring for \u003ccode\u003eAcroRd32.exe\u003c/code\u003e, \u003ccode\u003eAcrobat.exe\u003c/code\u003e, \u003ccode\u003eFoxitPhantomPDF.exe\u003c/code\u003e, and \u003ccode\u003eFoxitReader.exe\u003c/code\u003e spawning command-line interpreters or other suspicious utilities.\u003c/li\u003e\n\u003cli\u003eEnsure PDF reader applications are patched to the latest versions to mitigate known vulnerabilities.\u003c/li\u003e\n\u003cli\u003eImplement email filtering to block suspicious attachments and educate users about the risks of opening unsolicited PDF files.\u003c/li\u003e\n\u003cli\u003eMonitor network connections originating from PDF reader applications for unusual outbound traffic.\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-suspicious-pdf-child-process/","summary":"Adversaries may exploit vulnerabilities in PDF reader applications or use social engineering to execute malicious commands, often spawning system utilities for discovery or defense evasion purposes.","title":"Suspicious PDF Reader Child Process Execution","url":"https://feed.craftedsignal.io/briefs/2024-01-suspicious-pdf-child-process/"}],"language":"en","title":"CraftedSignal Threat Feed - Adobe Acrobat","version":"https://jsonfeed.org/version/1.1"}