Malicious PDF — malware analysis report

Static analysis result for SHA-256 36b1f955b50389cb…

MALICIOUS

PDF

69.1 KB Created: 2021-09-29 08:26:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 526c426c1353b2d54b02debebcb5417d SHA-1: a15b63ffbf4cc3901577ddb1ba7d6cacf97e4563 SHA-256: 36b1f955b50389cb3af707e2c830ffe1f7eba67ce4af75a78bfc289b0ab5cf9c
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates the PDF contains numerous links to disposable hosting, suggesting an attempt to obscure the true destination or spread malicious content across many domains. While no scripts were explicitly extracted, the presence of embedded URIs and the nature of the heuristics point towards a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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 https://maconlux.ovh/userfiles/files/sukifajegefila.pdf In PDF document text
    • https://worldkelo.com/wp-content/plugins/super-forms/uploads/php/files/0b5919a8236e00f75ee4f0ab092d6474/31167551222.pdfIn PDF document text
    • http://uniroll.pl/user_images/file/lomoxulopo.pdfIn PDF document text
    • http://koppeika.ru/userfiles/file/tidigunumewivijetolape.pdfIn PDF document text
    • http://bakefruit.com/uploads/files/202109151432248473.pdfIn PDF document text
    • https://www.la-providence-ehpad.fr/ckfinder/userfiles/files/dewowakokuletegi.pdfIn PDF document text
    • http://wxeina.com/userfiles/files/46892567812.pdfIn PDF document text
    • https://vasantviharproperties.com/userfiles/file/86323467521.pdfIn PDF document text
    • http://buyyoutubelikes.com/ci/userfiles/files/ruwuwegovomizuluk.pdfIn PDF document text
    • http://huseyindurmuslar.com/images_upload/files/81795551537.pdfIn PDF document text
    • http://www.77ice.com/upload/files/fewutuvaj.pdfIn PDF document text
    • https://gonguyenkhoi.vn/upload/files/76346333958.pdfIn PDF document text
    • http://shsuorui.com/uploadfiles/fckeditor/20210923/file/16324146635071.pdfIn PDF document text
    • https://altsovmun.ru/userfiles/file/muwumoxivubo.pdfIn PDF document text
    • https://jungleflightchiangmai.jungle-flight.com/Uploads/files/nonobaximabizofolupiwu.pdfIn PDF document text
    • http://fairfresh.net/assets/admin/ckeditorimage/files/90555013997.pdfIn PDF document text
    • http://ventima.ru/userfiles/file/ruduwosidifowopa.pdfIn PDF document text
    • https://cortemadera.com/wysiwygfiles/file/44922167070.pdfIn PDF document text
    • http://nriloan.jctoursandtravels.in/files/burilogubefibibo.pdfIn PDF document text
    • https://leo.tw/upload/ckeditor/files/tolufimenanilomuz.pdfIn PDF document text
    • http://dangkyidol.com/wp-content/plugins/super-forms/uploads/php/files/9s9jg2bmhnqvcvtrfdor91h91j/50971481844.pdfIn PDF document text
    • http://phdpecs.hu/userfiles/files/69989427007.pdfIn PDF document text
    • http://luligang.com/ckfinder/userfiles/files/75381045791.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=three+kinds+of+precipitationPDF 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_off0000afc7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAFC7 10724 bytes
SHA-256: c2293f9f287dbf40ee2aca61405a6edb52ffdfe0d99889879391726a69bc1805
font_01_sfnt_off0000c863.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC863 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e075.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE075 15208 bytes
SHA-256: 02b5defe31fc04914209c793531ce45ea7b92ef9af28739b6307b749ff48fed7