Malicious PDF — malware analysis report

Static analysis result for SHA-256 36b424c6656fbb72…

MALICIOUS

PDF

68.8 KB Created: 2021-09-27 10:27:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: eb6db77283b8db0abdd3ec007e0f2afb SHA-1: 5cfee97381c46dca63b6c68b6f79c8fe3dbe1724 SHA-256: 36b424c6656fbb7258dc7e79ed9521618415c5c0f878b3ae781de8b7c932c1f5
146 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF was identified as malicious by ML classifiers and ClamAV, with heuristics indicating it's an image-only lure designed to trick users. The document body is heavily obfuscated, but the presence of numerous external URIs, many pointing to PDF files on disposable hosting, strongly suggests a phishing or malware distribution campaign. The primary attack pattern involves tricking the user into clicking a malicious link within the document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9837

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Image-only document with action trigger (screenshot lure) medium PDF_IMAGE_LURE
    PDF has 1 image(s), only 0 text block(s), carries a click-outward action, and is only 68 KB — typical shape of a phishing lure where a full-page screenshot hides a clickable button that launches or submits to an attacker URL.
  • 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://n-production.com/upload/fckeditor/file/pipevataguxibibagefot.pdf In PDF document text
    • https://egokituz.org/files/galeria/files/64397219939.pdfIn PDF document text
    • http://matemotors.com/userfiles/file/duxexen.pdfIn PDF document text
    • http://dunajecbiala.pl/upload/File/41668933991.pdfIn PDF document text
    • http://www.darvidproperty.com/news/file/76137042387.pdfIn PDF document text
    • https://babetravelling.com/ckfinder/userfiles2/files/saxedapepa.pdfIn PDF document text
    • http://pietrek.com/MARCUS/files/file/reretujov.pdfIn PDF document text
    • http://www.weilandensemble.nl/ckfinder/userfiles/files/5528440727.pdfIn PDF document text
    • http://anhuishangbiao.com/upload_fck/file/2021-9-5/20210905070210513231.pdfIn PDF document text
    • http://gamecoast.by/uploads/files/wuzunafawurewate.pdfIn PDF document text
    • http://ateliergermain.club/sites/default/files/file/77809788990.pdfIn PDF document text
    • http://tabouligrill.com/ckfinder/userfiles/files/mabupudunomugakirike.pdfIn PDF document text
    • https://penzehir.com/dorceiys/ckfinder/userfiles/files/juxatoniserunixulotiras.pdfIn PDF document text
    • http://s-privod.ru/userfiles/file/75162076661.pdfIn PDF document text
    • https://ost-fogging.com/upload/files/zanexujekevepijaz.pdfIn PDF document text
    • http://www.ecrivains-consult.fr/easyonline/ckfinder/userfiles/files/97927423082.pdfIn PDF document text
    • http://everestlodgelukla.com/userfiles/file/26029000140.pdfIn PDF document text
    • https://livstyle.ro/home/livstyle/public_html/uploads/files/89729292786.pdfIn PDF document text
    • http://stagegator.scorchmark.com/stagegator/ckfinder/userfiles/files/3874421133.pdfIn PDF document text
    • http://alexdisinfestazioni.com/userfiles/files/26538834608.pdfIn PDF document text
    • http://metamorfoza-krosno.pl/userfiles/file/mategavinesopo.pdfIn PDF document text
    • https://feniks9.ru/ckfinder/userfiles/files/lobuxolopivim.pdfIn PDF document text
    • http://megalaserasia.com/upload///86551064437.pdfIn PDF document text
    • https://www.reparaciondebomba.com.ar/wp-content/plugins/super-forms/uploads/php/files/41d1edsgi50sds3fvlhjjrqcl1/20589365012.pdfIn PDF document text
    • https://kolkatanagariksammelan.org/ckfinder/userfiles/files/85268321521.pdfIn PDF document text
    • http://www.siscard.com/wp-content/plugins/formcraft/file-upload/server/content/files/16146c2805758f---lekosunur.pdfIn PDF document text
    • https://petikdaun.com/contents/files/jemib.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=android+package+installer+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_off0000b1d7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB1D7 14096 bytes
SHA-256: 118c08a37906f8c0e3630477c037d9699eca1f59459df9690a40157cce9c486b
font_01_sfnt_off0000d507.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD507 10760 bytes
SHA-256: fdc5485e19b98f089d4082e3ac2fab52ecb7c79898ba5ea486a6a128d10f34bb
font_02_sfnt_off0000edb6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDB6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1