Malicious PDF — malware analysis report

Static analysis result for SHA-256 ab61ba8b8fc617bc…

MALICIOUS

PDF

94.2 KB Created: 2021-09-11 18:20:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: c9dcd70f8eb5fef55028e4000aafc011 SHA-1: 50a8fbfac866585b83ef521be618ee74755f7438 SHA-256: ab61ba8b8fc617bc9ffe384f77ef21eb7fe813994de2926a1af7e19f5f66874e
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs pointing to disposable domains, characteristic of a link farm used for phishing or malware distribution. The ML classifier and ClamAV detection strongly indicate malicious intent. Although no scripts were explicitly extracted, the PDF structure and embedded URIs suggest it's designed to redirect users to malicious content, likely leveraging T1566.001 (Spearphishing Attachment) as the initial access vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9957

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://coretry.ru/uplcv?utm_term=free+followers+me+instagram PDF link annotation
    • http://basumati.com/app/webroot/ckfinder/userfiles/files/79884463394.pdfIn PDF document text
    • https://enkaotomatikkapi.com/depo/sayfaresim/file/zabepemumidejonupeli.pdfIn PDF document text
    • http://frutapac.es/ckfinder/userfiles/files/32895075398.pdfIn PDF document text
    • https://www.18fire.com/wp-content/plugins/super-forms/uploads/php/files/9298c8adfe7fe30c872397ed0576ab2a/9764320743.pdfIn PDF document text
    • http://pfmconsulting.org/survey/userfiles/files/selelizapepasuromo.pdfIn PDF document text
    • http://unternehmensberatung-hegenbarth.de/userfiles/file/barimelomejifak.pdfIn PDF document text
    • https://privatecambodiatour.com/userfiles/file/belesimajavur.pdfIn PDF document text
    • http://asdgolfclubtoscana.com/writable/public/userfiles/file/vavinefurilumuje.pdfIn PDF document text
    • https://webornate.com/viking1/uploads/files/kamuzob.pdfIn PDF document text
    • http://xn----0tbbbfo0f.xn--p1ai/userfiles/file/30283936646.pdfIn PDF document text
    • http://dentalcenterstudio.it/userfiles/files/lofov.pdfIn PDF document text
    • http://www.pantonerestauri.com/ckfinder/userfiles/files/93151774984.pdfIn PDF document text
    • http://stimatacasa.eu/userfiles/files/4333914058.pdfIn PDF document text
    • https://history.tlshaa.org.tw/ckfinder/userfiles/files/ronagaruwuxobagasakujuvez.pdfIn PDF document text
    • http://webinaris.net/ckfinder/userfiles/publics/files/3478579129.pdfIn PDF document text
    • http://www.nandomoraes.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161301fb938880---67176327700.pdfIn PDF document text
    • https://relaxbotanika.cz/ckfinder/userfiles/files/69829540927.pdfIn PDF document text
    • http://www.dawnrotaryclub.tw/UserFiles/files/dadifozeluwomuz.pdfIn PDF document text
    • https://sharks-cz.cz/images/file/rodanojumodoxokurekatabe.pdfIn PDF document text
    • http://elmbbq.com/uploads/files/zemevakoxekeg.pdfIn PDF document text
    • https://lingchuanfloor.com/app/webroot/userfiles/files/senibipaniki.pdfIn PDF document text
    • http://brilliantsolarpaneling.com/userfiles/file/venepapapuwuzopewanijira.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_off00010aec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10AEC 10620 bytes
SHA-256: b735a61f306a8eac82e81a99909e3010083dd0ba7fff42e8a26811cb8b8a8c22
font_01_sfnt_off0001233d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1233D 18652 bytes
SHA-256: 2bc223451c6357d3da6b71ed166f8ec6934012c556e418c12ea0695907dae18a
font_02_sfnt_off000153a6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x153A6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1