Malicious PDF — malware analysis report

Static analysis result for SHA-256 71cee20bf992dc7f…

MALICIOUS

PDF

70.0 KB Created: 2021-09-26 12:51:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 22c82224e29b59865c906c3416172818 SHA-1: 53811ca77db511f715b22a6a041934e1a04dd2e8 SHA-256: 71cee20bf992dc7f5e5642d8739a0f50ec877e9c152970007803e05c8aa4bc31
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous embedded URLs pointing to a link farm, as indicated by the PDF_SEO_DISPOSABLE_LINK_FARM heuristic. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were explicitly extracted, the nature of the embedded URLs and the link farm structure points towards a phishing or malware distribution scheme, likely initiated via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9893

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 http://baiduvpn.com/upload/files/pojiwagasexalokif.pdf In PDF document text
    • http://studiotecnicolamanna.com/userfiles/files/wamamozud.pdfIn PDF document text
    • https://begili.com/uploads/image/files/zibutomuwilirejepopejodiw.pdfIn PDF document text
    • http://vanillasky-ch.com/images/files/dirodiz.pdfIn PDF document text
    • http://www.neoneofitou.com/ckfinder/userfiles/files/31752241146.pdfIn PDF document text
    • http://andersonlawdecorah.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/furatemafavomojato.pdfIn PDF document text
    • https://rabudiagnostic.com/userfiles/files/pejivugibexu.pdfIn PDF document text
    • http://irina-beha.com/ckfinder/userfiles/files/33786892100.pdfIn PDF document text
    • https://trsbarriersdirect.com/wp-content/plugins/super-forms/uploads/php/files/2sluvgumjfuaahkccurf4s2rhu/87745075361.pdfIn PDF document text
    • http://julianowka.pl/ckfinder/userfiles/files/53477001994.pdfIn PDF document text
    • http://goodtraefarm.com/ckupload/files/47897949052.pdfIn PDF document text
    • https://kingwrapcarspa.com/upload/files/13454550467.pdfIn PDF document text
    • https://sunrise-photon.com/upfiles/editor/files/kajogu.pdfIn PDF document text
    • http://le-lemniscus-incandescent.fr/ckeditor/upload/files/sapejogelinakowomepako.pdfIn PDF document text
    • https://ezastupitelstvo.sk/editor_uploads/system/files/gokulezidujinutixas.pdfIn PDF document text
    • http://ontis.sk/editor_uploads/system/files/41426596619.pdfIn PDF document text
    • http://vititanon.com/user_img/files/nopuxarilijevufivixewofa.pdfIn PDF document text
    • https://mosaicopeoplecorporation.com/ckfinder/userfiles/files/61029070896.pdfIn PDF document text
    • http://ipceurope.eu/assets/file/74042104170.pdfIn PDF document text
    • https://koetec.com/home/~ptow/public_html/ckfinder/userfiles/files/21582344946.pdfIn PDF document text
    • https://umiyawoodworks.com/fckdb/userfiles/file/naxudivu.pdfIn PDF document text
    • https://lanjutpt1.com/contents/files/mafizubokiwafagigaledow.pdfIn PDF document text
    • http://schroniskoorzechowce.pl/ckfinder/userfiles/files/77024303501.pdfIn PDF document text
    • http://gyogytornasz.hu/editor_up/wedebaretopixebupop.pdfIn PDF document text
    • https://vico-immobilien.com/ckfinder/userfiles/files/zolozukekelux.pdfIn PDF document text
    • http://tuvanluatdanang.com/upload/ck/files/73150738335.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=mi+tv+stick+transfer+filesPDF 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_off0000b1b1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB1B1 10360 bytes
SHA-256: 1c55f8a10e0e7d5880da8581012d3be5c412852a2dfd6a71000b99f004c29c2e
font_01_sfnt_off0000c941.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC941 16128 bytes
SHA-256: 9711f3086208f08aad082302d1348d9b6092033bc2199deb214f0d2f69ef501e
font_02_sfnt_off0000f281.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF281 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1