Malicious PDF — malware analysis report

Static analysis result for SHA-256 a7908ebd44538145…

MALICIOUS

PDF

80.9 KB Created: 2021-09-14 07:12:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: fbb0c9a6309cf0f28b59d907d385668e SHA-1: d23ab6697a8662e930d490bcc3300371c82ca415 SHA-256: a7908ebd44538145f26e32a2b1739ea210c744a41ceb5c5dcb9d15f7ed771d66
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML and ClamAV as malicious, with heuristics indicating it functions as a link farm. The presence of numerous unknown URLs suggests an attempt to redirect users to potentially malicious sites. While no scripts were explicitly extracted, the PDF structure and the nature of the heuristics point towards a phishing or malware distribution attempt, likely initiated via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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://lapmaymn.samdigroup.vn/app/webroot/upload/files/52572463286.pdf In PDF document text
    • http://likebarcode.com/image/files/20210912_005540.pdfIn PDF document text
    • http://z-sinpro.com/upload/files/losigakokekolo.pdfIn PDF document text
    • https://kaskad-74.ru/images/uploads/fupunatikinigunafipane.pdfIn PDF document text
    • http://carrollcountylawyers.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/53776838388.pdfIn PDF document text
    • https://soroptimist.be/oldsite/intranet/ckeditor/ckfinder/userfiles/images/files/jurufoj.pdfIn PDF document text
    • https://ritascreation.com/userfiles/file/segidalosuxaxonenuju.pdfIn PDF document text
    • https://arbormaster.net/uploads/files/roredozumiwa.pdfIn PDF document text
    • https://designclarf.it/file/doluserefiki.pdfIn PDF document text
    • https://wecareprogram.org/images/file/40766550266.pdfIn PDF document text
    • http://zhongjiukeji.com/upload_fck/file/2021-9-11/20210911175452725463.pdfIn PDF document text
    • http://hockjoohin.com/admin/uploads/file/26086337414.pdfIn PDF document text
    • http://xetaihyundai.net/upload/files/12814914726.pdfIn PDF document text
    • http://tsg-vaganovskoe.ru/ckfinder/userfiles/files/74863321939.pdfIn PDF document text
    • http://stkvn.ru/wp-content/plugins/super-forms/uploads/php/files/4afddb754d03a64820e733ea4561bc39/rilizarikegotuwop.pdfIn PDF document text
    • http://mebco.ru/images/file/88399040864.pdfIn PDF document text
    • http://kyochonbuenapark.iorderfoods.com/uploads/files/931676194.pdfIn PDF document text
    • https://propactionvehiclesuk.tv/userfiles/files/vasasodukemapag.pdfIn PDF document text
    • http://jungvassar.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/98722188574.pdfIn PDF document text
    • http://kcntanduc.vn/img_duhoc/files/3995306542.pdfIn PDF document text
    • https://tecnicadovolante.com/images/file/lutem.pdfIn PDF document text
    • http://tichdiem.surecare.vn/uploads/userfiles/file/84164380145.pdfIn PDF document text
    • http://www.lentilles-progressives.fr/wp-content/plugins/formcraft/file-upload/server/content/files/161347e372f6a0---14881909601.pdfIn PDF document text
    • http://lex-ter.ru/admin/ckfinder/userfiles/files/sumirejikijupuxor.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=kranti+movie+mp3+song+downloadPDF 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_off0000d4d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4D5 18308 bytes
SHA-256: 3773ccae4a187a6c06e8479c933418eb086cb94ceaa5e7fec95d20cfc693eca0
font_01_sfnt_off00010491.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10491 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011ca8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CA8 11048 bytes
SHA-256: f81af887552212ba1d7a1f0bc511bc74b3533e1bd7e54b617c48f36ef85c6bd9