Malicious PDF — malware analysis report

Static analysis result for SHA-256 cd36c749d026b9e5…

MALICIOUS

PDF

78.8 KB Created: 2021-09-18 06:54:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: f01cf4862e851ccb934faaef4a1dcf24 SHA-1: 1e9036f51930cb19fe3faa4c72c8dea5254e2e84 SHA-256: cd36c749d026b9e5ffe6d60487389b001b7ad131f32b5f6c22d64ed956d55de3
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF document contains numerous embedded URLs and heuristics indicate it is a link farm, with one URL specifically mentioning 'mobile remote access android app'. The 'SE_REMOTE_SUPPORT_LURE' heuristic strongly suggests the document's intent is to trick the user into installing or using a remote support tool. This is a common tactic for gaining unauthorized access or delivering further malicious payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Remote-support tool lure high SE_REMOTE_SUPPORT_LURE
    Document instructs the user to install, open, or connect with a remote-support tool such as AnyDesk, TeamViewer, Quick Assist, or ScreenConnect — high-risk in an unsolicited document
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://smidgel.ru/uplcv?utm_term=mobile+to+mobile+remote+access+android+app PDF link annotation
    • https://abss.pt/userfiles/file/wuzek.pdfIn PDF document text
    • http://swaarm.de/app/webroot/upload/files/71146644666.pdfIn PDF document text
    • http://yummyschool.com/_UploadFile/Images/file/zedelokologoxezamaje.pdfIn PDF document text
    • https://betsin.org/userfiles/files/81084384989.pdfIn PDF document text
    • https://nedimgame.net/calisma2/files/uploads/nazoko.pdfIn PDF document text
    • http://partnercable.com/files/84463016017.pdfIn PDF document text
    • http://kondicionery-vidnoe.ru/upload_picture/file/84933962491.pdfIn PDF document text
    • https://lazdynumokykla.lt/userfiles/file/68349507042.pdfIn PDF document text
    • http://lscapital.it/images/file/gunirasituro.pdfIn PDF document text
    • http://agro-partner.com/Image/files/lidimopikepewurufekuri.pdfIn PDF document text
    • http://motorlustor.net/userfiles/file/ropusawotukupukef.pdfIn PDF document text
    • http://medicaldistri.com/ckfinder_files/files/40042075814.pdfIn PDF document text
    • http://ibookingkr.com/FileData/ckfinder/files/20210912_FC90A4001FE68260.pdfIn PDF document text
    • https://www.simplythebestevents.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1613032a943d29---nurepajafokenofur.pdfIn PDF document text
    • http://www.radanhorse.com/resource/files/78681765454.pdfIn PDF document text
    • http://mothertheresapublicschool.com/userfiles/file/16401238286.pdfIn PDF document text
    • http://studiofantino.it/userfiles/files/fobusisuvojerubawimex.pdfIn PDF document text
    • http://www.farparts.cl/wp-content/plugins/formcraft/file-upload/server/content/files/1613ef8e9744ab---89382730714.pdfIn PDF document text
    • http://tunesistudio.eu/userfiles/files/zaduvugonarowavizasazidej.pdfIn PDF document text
    • https://imapcb.org/wp-content/plugins/super-forms/uploads/php/files/7122f34bf5bb99151d7d4c7b11b1f937/bewakebasuw.pdfIn PDF document text
    • https://www.heainc.com/wp-content/plugins/formcraft/file-upload/server/content/files/161408fc21a605---vodizupibugeji.pdfIn PDF document text
    • https://happycustomerservice.com/wp-content/plugins/super-forms/uploads/php/files/26a057a2c04cd104c865378ee677543e/vumeso.pdfIn PDF document text
    • http://www.psoevalledeabdalajis.es/ckfinder/userfiles/files/37005064033.pdfIn PDF document text
    • https://rizecanreklam.com/images/file/34524439986.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000cde6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCDE6 10808 bytes
SHA-256: 51a241695d7ad60f386adc3c15abffe20f9c900d089ffc5d3b42c9e395cdb6ef
font_01_sfnt_off0000e687.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE687 17832 bytes
SHA-256: d5ae98b3c3801f90fe637467e68db4aaecc27f0d696a8fc7b3b4ad3d6ad26751
font_02_sfnt_off00011504.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11504 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1