Malicious PDF — malware analysis report

Static analysis result for SHA-256 70921efd00ae0f89…

MALICIOUS

PDF

83.4 KB Created: 2021-09-09 04:38:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: e0adaacb102329b9cfe882aff1ecfe55 SHA-1: 93f324135434b5591733079daeb09f366a180470 SHA-256: 70921efd00ae0f8932a00b398d32bb1cac4cedd0e29a1b060596fb1c61acd3d6
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ClamAV and an ML classifier, with heuristics indicating malformed exploit streams and a link farm structure. The embedded URLs and the 'QR code redirect lure' heuristic suggest the document's primary purpose is to trick users into visiting external sites, likely for phishing or malware distribution. No scripts were extracted, but the PDF structure itself facilitates the redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Malformed active-content stream length medium PDF_MALFORMED_EXPLOIT_STREAM_LENGTH
    A PDF stream that carries active/exploit-looking content has a declared /Length that does not match the recovered stream body. Malformed stream boundaries and length mismatches are common parser-evasion/supporting evidence around Reader exploit streams.
  • 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.
  • QR-code redirect lure medium SE_QR_LURE
    Document instructs the user to scan a QR code with a phone — consistent with QR phishing, but also common in legitimate documents
  • 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://crysiq.ru/uplcv?utm_term=qr+code+scanner+iphone+8 PDF link annotation
    • https://99shayari.in/userfiles/files/24246115260.pdfIn PDF document text
    • http://casinodanmarkjackpot.dk/userfiles/file/limunujimupupadetopebu.pdfIn PDF document text
    • https://leuphuotcamap.com/uploads/image/files/depududuferozejiboman.pdfIn PDF document text
    • https://bibliotheque.ville.deux-montagnes.qc.ca/ckfinder/userfiles/files/55307334052.pdfIn PDF document text
    • http://studiodabo.eu/userfiles/files/93258171588.pdfIn PDF document text
    • http://www.gdchgs.com/admin/img/files/89742931654.pdfIn PDF document text
    • https://festacontinua.it/public/file/29242170725.pdfIn PDF document text
    • http://aquamedia.cn/ckfinder/userfiles/files/92871366501.pdfIn PDF document text
    • http://linker-apps.com/files/tuzuxukozonakiforifux.pdfIn PDF document text
    • http://ateliergermain.org/sites/default/files/file/29930533061.pdfIn PDF document text
    • http://congtyvima.com/images/Download/poposegugexixiwewisofijiv.pdfIn PDF document text
    • https://aksukartela.com/images_upload/files/24148444083.pdfIn PDF document text
    • https://newsale.linyn.mobi/upload/ckeditor/pages/files/rakagidatubotexoditodu.pdfIn PDF document text
    • http://leebyunghun.kr/new/upload/board/files/joxetafotixododepetawaw.pdfIn PDF document text
    • http://xdata.pl/app/webroot/img/ckf/files/72665947162.pdfIn PDF document text
    • http://cargo3030.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1612e9a943d2c4---67885216453.pdfIn PDF document text
    • https://nurdagihaber.com/resimler/files/nijinesotikumim.pdfIn PDF document text
    • http://www.integra-cr.cz/administrace/ckfinder/userfiles/files/xobube.pdfIn PDF document text
    • http://vaithun.net/upload/files/tituwunitujulalirunivexe.pdfIn PDF document text
    • http://bhk-aindling.com/userfiles/files/vegutuzexurijijifikituz.pdfIn PDF document text
    • https://www.q-jin.ne.jp/ckfinder/userfiles/files/zisix.pdfIn PDF document text
    • http://emanuelmlevin.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/9139156312.pdfIn PDF document text
    • http://yalcinsezer.com/upload/ckfinder/files/punudenazokukexosekixu.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_off0000e121.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE121 10732 bytes
SHA-256: 5fec5cb0a9d69ac4ce46058ad499f6d4041a09f037248b4af1399d897f11ab2e
font_01_sfnt_off0000f9bd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9BD 17984 bytes
SHA-256: 7b837d657b293a946be13d306b0402ac538d5e1f0f015bb6a95821f60d4ec662
font_02_sfnt_off0001285e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1285E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1