Malicious PDF — malware analysis report

Static analysis result for SHA-256 53e04c3385e9c4e5…

MALICIOUS

PDF

84.3 KB Created: 2021-10-11 04:52:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: 43a3b3da5247ecfddea3078d4f32ec65 SHA-1: d8c74a2ed72640ea36e82c96c0b375c818a65450 SHA-256: 53e04c3385e9c4e52269e0f0d97f486b0a722bcfefdb5339a745738524cdbba7
126 Risk Score

Malware Insights

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

The PDF was flagged by ClamAV as Pdf.Phishing.Trojan and ML classifiers indicated maliciousness. It contains numerous embedded URLs, many pointing to other PDF files on distinct domains, suggesting a link farm designed to distribute malicious content or phish users. The heuristic PDF_SEO_DISPOSABLE_LINK_FARM further supports this, indicating a large number of links on disposable hosting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://lex.tj/img/file/22992769932.pdf In PDF document text
    • http://xn--80ab1a9a.xn--p1ai/sadm_files/56422316857.pdfIn PDF document text
    • https://www.rosebankprimary.co.za/inc/ckfinder/userfiles/files/10406638812.pdfIn PDF document text
    • http://spy-military-labs.com/userfiles/file/9791448571.pdfIn PDF document text
    • https://bisleri.genefied.co/ckfinder/userfiles/files/nazimowukowevi.pdfIn PDF document text
    • http://immobilieninvestors.net/userfiles/file/pinenomarigido.pdfIn PDF document text
    • http://ceraunavoltapizzeria.it/userfiles/files/gukuxadebodovedowukuwedad.pdfIn PDF document text
    • http://drivescuolaguida.it/userfiles/files/mubetavexozazorenoda.pdfIn PDF document text
    • http://miskolciharsona.hu/pictures/file/86611237274.pdfIn PDF document text
    • http://triumphtoday.org/wp-content/plugins/formcraft/file-upload/server/content/files/1613d0a863fc10---boviviwetilinufetefitonu.pdfIn PDF document text
    • http://fujiya-la.com/uploads/files/lasuxisonezunevipixutapu.pdfIn PDF document text
    • http://stellarvvv.ru/ckfinder/userfiles/files/59462924986.pdfIn PDF document text
    • http://werkschoenenverkoop.nl/images/docman/files/naxokowonikaxarejemiwagem.pdfIn PDF document text
    • https://cryptobasics.biz/uploads/files/jubuxawogezegabitisuvolij.pdfIn PDF document text
    • http://benjapakee.net/UserFiles/File/32622903564.pdfIn PDF document text
    • http://isagenixmakessense.com/ckfinder/userfiles/files/towixojaxonobeloxura.pdfIn PDF document text
    • https://estidevelopers.com/wp-content/plugins/super-forms/uploads/php/files/a320469afa094a344eb25ead57b9dcf5/93423689427.pdfIn PDF document text
    • https://doan295doson.vn/namthuan/images/news/files/31928734227.pdfIn PDF document text
    • http://leadingedgecorporate.com/user_images/file/wakepinulevusuvudizi.pdfIn PDF document text
    • http://antitumor.org/filespath/files/20210907181510.pdfIn PDF document text
    • https://holocaustresearch.pl/nowy/photo/file/51940466120.pdfIn PDF document text
    • http://canxetaidientu.com/images/file/23939239497.pdfIn PDF document text
    • https://ourguarantees.com/userfiles/file/36580147491.pdfIn PDF document text
    • https://thebookonpersonaltransformation.com/FCKeditor/file/kutaranutenekaf.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=appeal+against+temporary+injunction+orderPDF 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_off0000e349.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE349 17744 bytes
SHA-256: dd0d47ac919d20bcdf1bcea1b894f62a9d1474fa25311547625b91f19f9761ab
font_01_sfnt_off0001113c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1113C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012953.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12953 11184 bytes
SHA-256: 616614b1d4a24705f0bc9fe04aed70c6a2228290810bda4296ffa65a6fc56a8b