Malicious PDF — malware analysis report

Static analysis result for SHA-256 dc4f87459011bba9…

MALICIOUS

PDF

79.4 KB Created: 2021-09-22 14:54:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: d73528ef82b99c4c489979735071f41f SHA-1: b11f382394645eeca69920637a9725e7f1c1cfa8 SHA-256: dc4f87459011bba9e8633ed335c10b9605da5ca962da52058593d188bf1d52c6
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with many embedded URLs pointing to various domains, some of which are hosted on compromised CMS upload storage. The document body is unreadable, suggesting it may contain obfuscated content or exploit code.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://kronospan-mofa.hu/editor_up/87893198524.pdf In PDF document text
    • https://vespaclubcagliari.com/userfiles/file/lubitozutiwavuje.pdfIn PDF document text
    • https://adikmanis.com/contents/files/jatak.pdfIn PDF document text
    • http://dreamcatcherltd.com/userfiles/file/95750289752.pdfIn PDF document text
    • http://studiorapizza.it/userfiles/files/96081497078.pdfIn PDF document text
    • https://swimproject.eu/wp-content/plugins/super-forms/uploads/php/files/b9cd86dd3f0bfefeb778e8eb81f33c65/vilijoguk.pdfIn PDF document text
    • http://st03.it/userfiles/files/40239349297.pdfIn PDF document text
    • https://uslugiinzynierskie.com/eurostyl/photos/file/lubipajute.pdfIn PDF document text
    • http://onthebroadway.com/CPD/adminpanel/upload/file/fuzubajal.pdfIn PDF document text
    • http://xn----8sbemnkjd7bfu.xn--p1ai/design/img/upload/file/26858272522.pdfIn PDF document text
    • http://www.drop-lok.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ebf997babc---24717094586.pdfIn PDF document text
    • https://jotekonybakterium.hu/userfiles/files/4892242726.pdfIn PDF document text
    • http://alt-1c.ru/userfiles/file/fefosedetuwutolabikulali.pdfIn PDF document text
    • https://miamivanservice.net/wp-content/plugins/formcraft/file-upload/server/content/files/16144cedf5c793---pefelojoje.pdfIn PDF document text
    • http://chelseacarpet.com/ckfinder/userfiles/uploads/35022400107.pdfIn PDF document text
    • http://tfh-filter.hu/_user/file/43154166385.pdfIn PDF document text
    • https://ph2020.org/ckfinder/userfiles/files/56399194751.pdfIn PDF document text
    • http://www.peritaonline.es/ckfinder/userfiles/files/4752711837.pdfIn PDF document text
    • http://pedraferro.com/files/files/75436196190.pdfIn PDF document text
    • https://kligi.viart.lt/ckfinder/userfiles/files/35519414146.pdfIn PDF document text
    • http://www.taxivanclass.com/uploads/ckfinder/files/sugegas.pdfIn PDF document text
    • http://abwingstop.com/uploads/files/83146459642.pdfIn PDF document text
    • http://thenext.pk/userfiles/files/33878970.pdfIn PDF document text
    • http://louisamerino.com/userfiles/file/berexinawesozek.pdfIn PDF document text
    • https://ibliberia.com/ckfinder/userfiles/files/kakobudonevu.pdfIn PDF document text
    • https://lideregitimpaketleri.com/calisma2/files/uploads/48894490047.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=legend+of+legaia+ps1+isoPDF 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_off0000d341.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD341 10484 bytes
SHA-256: 1ba58a5b7a300473a9dd319427d264b93d5a3cf23920aff229455b76dac15592
font_01_sfnt_off0000eafa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEAFA 17388 bytes
SHA-256: a65366ddf9fb9f34b94c272e714273e8cd4ba8f8172f553efd00e21cf237e221
font_02_sfnt_off000117d4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x117D4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1