Malicious PDF — malware analysis report

Static analysis result for SHA-256 581cac4bedde815f…

MALICIOUS

PDF

69.3 KB Created: 2021-09-27 22:51:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: cda10baaeaf3234d94139f3f05a6543a SHA-1: 77b53c89fb9bf8e3d96f095f2e6e577161af9858 SHA-256: 581cac4bedde815f46c270e6559d72936cd2595fd7eb7ec4590408009ef56f76
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing or trojan. Heuristics indicate it functions as a link farm, directing users to numerous distinct domains, many of which are unknown or potentially disposable. The presence of many embedded URLs, despite some being marked benign, supports the conclusion that the primary function is to redirect users to external content, likely for malicious purposes such as credential harvesting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9950

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://minisadik-margaritka.ru/admin/ckfinder/userfiles/files/5478811797.pdf In PDF document text
    • http://alpha-cp.com/userfiles/file/31533575220.pdfIn PDF document text
    • http://c-six.it/userfiles/files/80301481507.pdfIn PDF document text
    • https://mwasafat.com/uploads/files/siwisojexejurutu.pdfIn PDF document text
    • https://sukhayurveda.in/userfiles/file/59372449869.pdfIn PDF document text
    • http://xlpe.net/Images_upload/files/gifaw.pdfIn PDF document text
    • https://www.opsclown.it/ckfinder/userfiles/files/87749843062.pdfIn PDF document text
    • https://kimcert.org/E/file/38169624412.pdfIn PDF document text
    • http://saveursetsavoirs.fr/image/file/68885750959.pdfIn PDF document text
    • http://stamforgtechnologies.com/uploads/vevirezafulafuvesasow.pdfIn PDF document text
    • http://npi-management.fr/ressource/site-image/files/dowas.pdfIn PDF document text
    • http://baiduvpn.com/upload/files/sibajasowadefenabulexi.pdfIn PDF document text
    • https://vleek.com/uploads/files/senesolaz.pdfIn PDF document text
    • http://www.derbysignandgraphics.com/uploads/file/vugesurunibuwonitidit.pdfIn PDF document text
    • http://dainichiji.com/upload_ckr/files/puserogebejip.pdfIn PDF document text
    • https://floresdeserrezuela.com/aym_image/files/fusegabivutovogopebegi.pdfIn PDF document text
    • https://pecintajp.com/contents/files/zosurijovexufojawuro.pdfIn PDF document text
    • http://iact2001.com/userData/board/file/mesatividazazemajaba.pdfIn PDF document text
    • http://archgeo-leszno.pl/uploads/userfiles/files/35403548135.pdfIn PDF document text
    • http://italiangreyhound.pl/img1/userfiles/file/51332931565.pdfIn PDF document text
    • http://www.putnamtaxi.net/wp-content/plugins/formcraft/file-upload/server/content/files/1613b0f4b396f4---natixogas.pdfIn PDF document text
    • http://adice-area.com/pictures/files/betazavekoli.pdfIn PDF document text
    • http://pizzeria-millemiglia.de/app/webroot/img/editor/file/55990976951.pdfIn PDF document text
    • https://www.18fire.com/wp-content/plugins/super-forms/uploads/php/files/4bab3b3fb1942c9ab49c85559c8cdd15/lazibibemoviregevuvimu.pdfIn PDF document text
    • http://www.elmundodelapiscina.com/ckfinder/userfiles/files/14391536524.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=chrome+tab+list+view+androidPDF 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_off0000af9d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAF9D 10836 bytes
SHA-256: b443f85c48ce0ffd30314c0c9b9c39b912a71a7dc4d4933030ba6b39e4266d74
font_01_sfnt_off0000c87c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC87C 14932 bytes
SHA-256: 0abc6388e68156ff10ebd5189f102a59d6182da9ef277321906903aab8522ccc
font_02_sfnt_off0000ee0d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE0D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1