Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac71185d44bf7092…

MALICIOUS

PDF

100.9 KB Created: 2021-09-17 02:59:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 1bcb7679991d104e262c4585ada71b35 SHA-1: fca3b0132e36c4dac02870c05e38b367ed1e342b SHA-256: ac71185d44bf7092dfdd03f46f9852b3377e60f68b2ddce5b45eefafe2f08829
176 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9877

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
  • 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.
  • QR-code redirect lure medium SE_QR_LURE
    Document instructs the user to scan a QR code with a phone — consistent with QR phishing, but also common in legitimate documents
  • 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 http://refinerlink.com/userfiles/file/88822212369.pdf In PDF document text
    • http://sabaispa.net/userfiles/file/gurisenerezuwo.pdfIn PDF document text
    • http://ourdesign.hk/ckfinder/userfiles/files/7626274867.pdfIn PDF document text
    • http://mskabel.cz/UserFiles/File/kafagurelujuxav.pdfIn PDF document text
    • https://www.growxponential.com/wp-content/plugins/super-forms/uploads/php/files/52drcqe0ek6e2em93afrqkebgr/45037838619.pdfIn PDF document text
    • http://lavera.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613b9c50f28e2---95287050171.pdfIn PDF document text
    • http://xhiehchin.com/Xhieh_News/_file/gedigosopitomegepob.pdfIn PDF document text
    • http://vindindex.nl/images/uploads/nedusezagakilajodovu.pdfIn PDF document text
    • https://tauthuy.vn/upload/files/6514551386.pdfIn PDF document text
    • http://altadirezione-consulting.it/userfiles/files/86278246056.pdfIn PDF document text
    • https://rosedreamholidayhomes.com/ckfinder/userfiles/files/81803573586.pdfIn PDF document text
    • https://jazykovytabor.topenglish.sk/app/webroot/gallery/files/bujimabimuzigob.pdfIn PDF document text
    • http://www.petersonassoc.com/emailimages/file/tudafokenawirubi.pdfIn PDF document text
    • http://natinsel.com/imagenes/file/5676545678.pdfIn PDF document text
    • http://lmalaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/9868000577.pdfIn PDF document text
    • http://www.absolutecateringla.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138d678bcad4---zilovudaxemik.pdfIn PDF document text
    • https://vleek.com/uploads/files/78588593030.pdfIn PDF document text
    • http://ltmetal.com/userfiles/files/83568964125.pdfIn PDF document text
    • https://alkathirilaw.com/userfiles/files/49313064653.pdfIn PDF document text
    • http://standdominica.org/files/files/tipinodep.pdfIn PDF document text
    • http://vigova.vn/Images_upload/files/86630307188.pdfIn PDF document text
    • http://progettarecasa.com/userfiles/files/puzokoralidotuj.pdfIn PDF document text
    • http://thelonerangerfanclub.com/ckfinder/userfiles/files/jupanalasimozanekezomebel.pdfIn PDF document text
    • https://www.tonygssoulfood.com/wp-content/plugins/super-forms/uploads/php/files/32541a7bd40f1dfff3f467715a63d160/jobedim.pdfIn PDF document text
    • https://vaynhanh365.net/contents/files/89789372226.pdfIn PDF document text
    • http://www.trisad.kz/ckfinder/userfiles/files/rudajoz.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=super+mario+64+ds+download+apkPDF link annotation
    • 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_off00011e28.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E28 11052 bytes
SHA-256: 4d0a00a97c9579df886b3abe37bf5aaec644bd9cb56d92066be3a8d0157a6334
font_01_sfnt_off000137ea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x137EA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00014ffc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14FFC 20252 bytes
SHA-256: e476df522fabe4de2a634e51c39bf54b29588d9d33b0da459dca30da8dc5b0ec