Malicious PDF — malware analysis report

Static analysis result for SHA-256 3661f367a8c218cf…

MALICIOUS

PDF

74.7 KB Created: 2021-09-14 04:18:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: f6c010f9b2ee71a82308c4e0260c1293 SHA-1: 00d40b7fb4477e81c2014dc075c254ab0a26fa74 SHA-256: 3661f367a8c218cfb114c9dc4477a820a830a3c9ab665ecc630c6a32bce5b57d
126 Risk Score

Malware Insights

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

The sample was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, many pointing to unknown or potentially malicious domains, suggesting it functions as a link farm or phishing lure. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating a tactic to distribute links across disposable hosting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9908

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 https://cruiseship.cruises/wp-content/plugins/super-forms/uploads/php/files/d41p6nrrmvv2d3rgfvpgkrs0d6/fiderajuwopaxolobef.pdf In PDF document text
    • http://sofia-es.tokyo/yamituki-n/uploads/files/rumazotoxozikosiki.pdfIn PDF document text
    • https://digicpictures.com/downloads/gomorazawokisebes.pdfIn PDF document text
    • http://olympicthesportshop.in/uploads/21614860641.pdfIn PDF document text
    • http://hkxhjfc.ltd/uploads/files/20210913171212.pdfIn PDF document text
    • http://parcroyale.hk/userfiles/504517319.pdfIn PDF document text
    • http://eugensa.lt/app/webroot/uploads/userfiles/files/wekokudakun.pdfIn PDF document text
    • http://shijijiaming.net/filespath/files/20210907110319.pdfIn PDF document text
    • https://sidexsideaudio.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139123a2f1b9---44598235006.pdfIn PDF document text
    • http://mehmetrasimmutlu.com/icerik/file/mamogiteji.pdfIn PDF document text
    • http://confidenzacsapagy.hu/upload/17886935685.pdfIn PDF document text
    • http://apple888.vn/luutru/files/pukasuxolas.pdfIn PDF document text
    • http://skupka54.ru/upload/m/51205027361.pdfIn PDF document text
    • http://thegoshow.net/userfiles/file/zurulonivixabuwur.pdfIn PDF document text
    • http://kbchina.de/upload/wiludopuwisuliz.pdfIn PDF document text
    • http://ofitecnic.es/files.ofitecnic/fck_up/file/fumonezojeg.pdfIn PDF document text
    • http://efeotokiralama.com/Upload/file/15592110272.pdfIn PDF document text
    • https://piti.leaddeehub.com/userfiles/files/kuriromabedevitix.pdfIn PDF document text
    • https://bikeid.net/ckfinder/userfiles/files/raduwatuvokamalo.pdfIn PDF document text
    • https://gertiesbloomers.com/kousumi/nulook/upload/fckimages/file/98876990792.pdfIn PDF document text
    • http://gk-eventus.ru/admin/ckfinder/userfiles/files/duzukigo.pdfIn PDF document text
    • http://fotosvatba.net/userfiles/file/26622160392.pdfIn PDF document text
    • https://ecohort.com/userfiles/files/tevilozoruwisedofub.pdfIn PDF document text
    • https://asiantms.com/ckfinder/userfiles/files/50577251969.pdfIn PDF document text
    • http://jfhcoaching.com/userfiles/files/tobesat.pdfIn PDF document text
    • http://legalinet.eu/userfiles/files/bisofa.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=read+a+court+of+wings+and+ruin+pdfPDF 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_off0000c2f8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC2F8 15836 bytes
SHA-256: 74335ba9350327e578a5903e76600ca7c2a09bc598282d25b4d756489d898066
font_01_sfnt_off0000eb71.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB71 10980 bytes
SHA-256: 57ad43acf04c9a47f28eb833cf0461a006a8f8a574a87cab72cf1366c9c9bbaa
font_02_sfnt_off000104e9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104E9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1