Malicious PDF — malware analysis report

Static analysis result for SHA-256 e3bbb8994d89f2bd…

MALICIOUS

PDF

85.6 KB Created: 2021-10-08 07:52:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 040a09d4bd602c3bbabd537ff875df6f SHA-1: a4d49bbb5a6d31cff5b20956e50448a00e0d51b0 SHA-256: e3bbb8994d89f2bdafdd5dc65bef4559013ba870f859dfdd7bc799d459155a48
126 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, containing numerous embedded URLs pointing to other PDF files hosted on various domains. The primary purpose appears to be directing users to potentially malicious content through a deceptive link structure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

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 http://top-caster.com/userfiles/file/51163074267.pdf In PDF document text
    • https://radio-clipa.ro/userfiles/file/xipibavokaxovojomug.pdfIn PDF document text
    • http://uni-farm.pl/ckfinder/userfiles/files/femebuzidezekirofatewusi.pdfIn PDF document text
    • http://trlgpc.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/99569266568.pdfIn PDF document text
    • https://newat.ru/wp-content/plugins/super-forms/uploads/php/files/3487f54acdde016bf8686127e7e3527d/zojekesopuretofunuledunex.pdfIn PDF document text
    • https://siriusdynamics.com/assets/uploads/files/devewapojelu.pdfIn PDF document text
    • http://mopi.eu/ckfinder/userfiles/files/17196564109.pdfIn PDF document text
    • http://zzzwchem.com/upload/files/48804477787.pdfIn PDF document text
    • https://highlander-inn.com/assets/userfiles/files/voxezapibewumomuzok.pdfIn PDF document text
    • http://liubeauty.com/luutru/files/14930797235.pdfIn PDF document text
    • http://ingmontagna.com/userfiles/files/zuxuduwitoro.pdfIn PDF document text
    • https://excore.hu/ckfinder/userfiles/files/nitad.pdfIn PDF document text
    • http://anapro.com/ckfinder/userfiles/files/xaponugotavonusotap.pdfIn PDF document text
    • https://gtsonline.nl/wp-content/plugins/super-forms/uploads/php/files/i65emkgioeiva4ufd307j2dlni/897914540.pdfIn PDF document text
    • http://immopolignano.lu/images/lemisexabexiketefimos.pdfIn PDF document text
    • http://fcvperu.org/data/fcvperu/userfiles/file/wuwagawesetewatusibamijiz.pdfIn PDF document text
    • http://heizler.hu/files/file/5804838195.pdfIn PDF document text
    • https://pacificengineering.co/imagenes_cont/sitio/documentos/58737861564.pdfIn PDF document text
    • http://archinfo.ru/uploads/file/kebadoberimawopejo.pdfIn PDF document text
    • http://ghespanail.com/fckeditor_userfiles/file/10416809383.pdfIn PDF document text
    • http://tvoirostov.ru/ckfinder/userfiles/files/87350885457.pdfIn PDF document text
    • http://www.dfdtrading.sk/ckfinder/userfiles/files/96696316440.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=pre+indictment+meaningPDF 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_off0000e93f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE93F 18680 bytes
SHA-256: df2d4baaf2072626ac91f07fd15a195e93541e260e7e2d7d9a5723b5acef08f4
font_01_sfnt_off000119ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x119FF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013216.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13216 10380 bytes
SHA-256: efcdfb550e6b055c3634271c7764acb50cbf68dd2751e43259d73949227f15fe