Malicious PDF — malware analysis report

Static analysis result for SHA-256 6b582576e8cd45c8…

MALICIOUS

PDF

93.4 KB Created: 2021-10-15 14:37:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 53aa2e9b72659404c5b9ad115bee7f77 SHA-1: 92609a440ac61928c127d95f0d2aa0011c2de1d4 SHA-256: 6b582576e8cd45c80261f02444b16bc018a4003f05d5955d22e7bdd2dda09369
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains a large number of embedded URLs, many pointing to unknown PDF files hosted on potentially disposable domains, suggesting a link farm or phishing lure. The `PDF_SEO_DISPOSABLE_LINK_FARM` heuristic further supports this, indicating an attempt to distribute or redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9820

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 http://defhjdrjioo.friend-match.com/upload/files/nukexipevol.pdf In PDF document text
    • https://chiuman-hk.com/images/file/vetovawejujunanovemawo.pdfIn PDF document text
    • http://bawaconstructions.com/editorData/file/93404354761.pdfIn PDF document text
    • http://dj-venci.com/uploads/pages/files/waxilibetibosumom.pdfIn PDF document text
    • http://ranczowdolinie.com/files/vipolugesox.pdfIn PDF document text
    • http://rockhousemethod.com/ckfinder/userfiles/files/61341690091.pdfIn PDF document text
    • http://zenobiacultura.it/userfiles/file///75107855231.pdfIn PDF document text
    • http://gelateriacool.it/userfiles/files/koxamunosesizuniloj.pdfIn PDF document text
    • http://fotografoenricogiampieri.it/userfiles/files/patogidapumubar.pdfIn PDF document text
    • http://darec.sk/files/files/42720191128.pdfIn PDF document text
    • https://centrorevisionimonregalese.it/file/xaxiw.pdfIn PDF document text
    • http://matsonconstruction.net/userfiles/file/xosotelikivobovewopokez.pdfIn PDF document text
    • https://stef-nancy.fr/upload/document/xofaregobabosaseled.pdfIn PDF document text
    • https://choosetop.e-giant.net/fkupload/files/jefotudebugumakure.pdfIn PDF document text
    • http://cu-hinothai.com/ckfinder/userfiles/files/27619689364.pdfIn PDF document text
    • http://webhoctot.com/app/webroot/uploads/files/gasut.pdfIn PDF document text
    • https://triatlonshop.cz/userfiles/file/sexoti.pdfIn PDF document text
    • http://elencostruzioni.it/userfiles/files/fupisebupofofexisag.pdfIn PDF document text
    • http://donovaly-ubytovanie-safran.sk/web/userfiles/file/keliroror.pdfIn PDF document text
    • http://www.rarlaw.net/siteuploads/editorimg/file/siwazaduz.pdfIn PDF document text
    • http://xn----7sbqwxdbhblh2h.xn--p1ai/data/file/9008883124.pdfIn PDF document text
    • https://www.davidcosz.de/wp-content/plugins/super-forms/uploads/php/files/f57l3h6osfd6nulkjasnmfjasf/rikixuji.pdfIn PDF document text
    • http://siamsnail.com/media/userfiles/files/vujusowe.pdfIn PDF document text
    • http://panyuchen.com/ckfinder/userfiles/site_eachfun_com/files/38349405856.pdfIn PDF document text
    • http://www.restorationservice.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1613af3b504392---91257075531.pdfIn PDF document text
    • http://lltsg.com/uploadfile/file///2021090605482369.pdfIn PDF document text
    • http://feedproxy.google.com/~r/MbOu/~3/vItLtdF7Pec/uplcv?utm_term=modern+indian+history+practice+bits+in+teluguPDF 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_off000101a6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x101A6 21612 bytes
SHA-256: 1886aa3fa43bcb05d98f6ad20665b8ad1fb6c04018a6e1b6cf880648cf5e8606
font_01_sfnt_off000135ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x135FF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00014e16.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14E16 11140 bytes
SHA-256: 9f0fea386c58b3f4318612b22ec6374149248da3e04a3680725fb88c8f5f4707