Malicious PDF — malware analysis report

Static analysis result for SHA-256 86945e9a81d2d837…

MALICIOUS

PDF

69.8 KB Created: 2021-10-02 22:25:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: a3eaa1c64102a7859419b3aad9493013 SHA-1: a211dc05cf90ede341528e4b3fdedb818951161e SHA-256: 86945e9a81d2d837de74772500e75b1f1480dbc21842a558237cfffe700c23e8
126 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many pointing to disposable domains, and is flagged by heuristics as a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic specifically identifies the sample as a link farm on disposable hosting, suggesting a tactic to obscure the true malicious destination.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9954

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://tmtteks.com/files/zosekizibifavulutiwe.pdf In PDF document text
    • https://myreply.mobi/snappshott/editor//file/vavubijazu.pdfIn PDF document text
    • http://mgtofubbq.com/uploads/files/latonovivojozegaw.pdfIn PDF document text
    • http://cl-pub.com/files/files/kufaxupobobi.pdfIn PDF document text
    • http://www.s4b.nl/upload/files/leseri.pdfIn PDF document text
    • http://h-st.nl/bestanden/files/vupusewesipozedidezekexer.pdfIn PDF document text
    • https://epagneuls-bretons.fr/caningest/images/file/34009109123.pdfIn PDF document text
    • http://skkouty.cz/ckfinder/userfiles/files/gidigatoletapevalimowe.pdfIn PDF document text
    • http://informerfitness.com/wp-content/plugins/super-forms/uploads/php/files/9522e2c0eeae3ce30a5d9a3127533a63/12898182702.pdfIn PDF document text
    • http://pospatrans.cz/UserFiles/File/3279854303.pdfIn PDF document text
    • https://questyme.com/userfiles/file/vonufulegodasobewak.pdfIn PDF document text
    • http://lesbambousbleus.fr/ckeditor/upload/files/gulunajiwokam.pdfIn PDF document text
    • http://thestarbusan.net/FileData/ckfinder/files/20210911_E12A3838A30D28B6.pdfIn PDF document text
    • https://qwert5.com/psum/admin/userfiles/file/48098716277.pdfIn PDF document text
    • http://trineckevzdelavani.cz/webpagebuilder/ckfinder/userfiles/files/32759498958.pdfIn PDF document text
    • http://huile-de-nigelle.info/userfiles/file/fupazoronowodonuvuj.pdfIn PDF document text
    • http://archinfo.ru/uploads/file/pozidopododiremetokediw.pdfIn PDF document text
    • https://bellcera.60km.com/upload/files/dumol.pdfIn PDF document text
    • http://www.espace-hotelier.com/ckfinder/userfiles/files/91567857823.pdfIn PDF document text
    • http://czpohledavky.cz/userfiles/files/wazuxonawakevitunobubag.pdfIn PDF document text
    • http://uzks.hr/upload/datoteke/wupovujuxikelufesupulafoj.pdfIn PDF document text
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/16150189a628dd.pdfIn PDF document text
    • http://remont-m.com/userfiles/file/wiradajitejajuraz.pdfIn PDF document text
    • https://www.hkha.org/ckfinder/userfiles/files/72325371380.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=similes+and+metaphors+in+the+grinch+song+answersPDF 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_off0000afbc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAFBC 11120 bytes
SHA-256: d52c1293e72d69b893bdd4398f9b9cc2981e53c98987248fbe4b50ec6a6d8381
font_01_sfnt_off0000c949.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC949 15148 bytes
SHA-256: 909fd4f3c962a9d7e65d80df50202518720b9d11facd74a28470b90ae628af35
font_02_sfnt_off0000ef7d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF7D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1