Malicious PDF — malware analysis report

Static analysis result for SHA-256 3fe28d5fb35cdce5…

MALICIOUS

PDF

88.1 KB Created: 2021-09-10 12:17:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: f0d5a4268db0e3a16c3edf03ec6f8188 SHA-1: b93404e3a9f6108f814fba51eba565ea317125a1 SHA-256: 3fe28d5fb35cdce56b574c737af306e494ad1bfd4cc4e93864227a45d5b5b41c
126 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to disposable hosting and are part of a link farm, a common tactic for phishing or distributing further malware. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the PDF structure and URL patterns suggest it's designed to lure users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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 https://chcial.ru/uplcv?utm_term=aplicativos+google+android PDF link annotation
    • http://net-work.cz/data/file/sotodawexogu.pdfIn PDF document text
    • http://heimundsicherheit.de/userfiles/file/gixamadigosewazozegex.pdfIn PDF document text
    • http://srihemkuntsahibfgp.org/hemkunt/userfiles/file/wudugixuvaxes.pdfIn PDF document text
    • https://livbiopharma.com/userfiles/file/debifexaxezuvafufix.pdfIn PDF document text
    • https://www.oalysa.cz/ckfinder/userfiles/files/27945585319.pdfIn PDF document text
    • https://rimi.sk/userfiles/file/30562139484.pdfIn PDF document text
    • http://harckocsik.hu/userfiles/file/fofutazetatemifoju.pdfIn PDF document text
    • http://efeotokiralama.com/Upload/file/25323181030.pdfIn PDF document text
    • http://cbcom.eu/ressource/site-image/files/nebipok.pdfIn PDF document text
    • http://www.stadion-zarya.ru/ckfinder/userfiles/files/vixawi.pdfIn PDF document text
    • http://fnathservices.com/upload/file/54676162336.pdfIn PDF document text
    • https://www.tzounakos-insurance.gr/ckfinder/userfiles/files/49134046197.pdfIn PDF document text
    • http://dilimkebab.com/userfiles/file/63564257378.pdfIn PDF document text
    • https://edu-mate.kr/_UploadFile/Images/file/dagubowidugadasorane.pdfIn PDF document text
    • https://www.benkorner.nl/admin/library/ckfinder/userfiles/files/ropavuxosave.pdfIn PDF document text
    • https://terracetemayonetim.com/upload/ckfinder/files/denibe.pdfIn PDF document text
    • http://plantessentialoil.com/upload/files/wofizadokumemu.pdfIn PDF document text
    • http://juentai.com/userfiles/files/11118953013.pdfIn PDF document text
    • https://miamivanservice.net/wp-content/plugins/formcraft/file-upload/server/content/files/1613248a450d18---dalaxovafawibililenet.pdfIn PDF document text
    • https://mission4recruitment.com/wp-content/plugins/formcraft/file-upload/server/content/files/161317f9e9f1eb---livezulakusasilimilinozaj.pdfIn PDF document text
    • http://kanoonkaraj.ir/dbmanager/filebank/htmlgallery/file///muvevuxexaz.pdfIn PDF document text
    • http://medwin.kr/userData/board/file/kikoraluvizumid.pdfIn PDF document text
    • http://arsvet.ru/img/upload/jawuwisujab.pdfIn PDF document text
    • http://turnwealthy.com/ckfinder/userfiles/files/53779423991.pdfIn PDF document text
    • https://profitaler.com/UserFiles/file/68420037867.pdfIn PDF document text
    • http://frigotechreina.com/userfiles/files/80840657591.pdfIn PDF document text
    • http://kingswaytyres.com/project/kingsway/uploads/file/gifazo.pdfIn PDF document text
    • https://elsadaulte.com/ckfinder/userfiles/files/kimufesekebux.pdfIn PDF document text
    • 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_off0000f470.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF470 17468 bytes
SHA-256: e1f1696c5d0e0a9c8a7c395631b7e16aeadd3c20289efae075246527d5ca7d9a
font_01_sfnt_off000121f3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121F3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013a0a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13A0A 10736 bytes
SHA-256: af8bc815d1c1b9acc2cf17087da3bb04d77df24fb5283c40d61cce717aa7e363