Malicious PDF — malware analysis report

Static analysis result for SHA-256 cd5cf3af7daa5aee…

MALICIOUS

PDF

76.0 KB Created: 2021-09-30 20:44:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 2c123c93aa98770427c9d0c3197f98c9 SHA-1: b3e65df526cf3b6961c74cafa6f73a929d8caecb SHA-256: cd5cf3af7daa5aee2cd6c9e3144373adfc08ff7dd8a960727161f40e391ee814
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, with several heuristics indicating it functions as a link farm on disposable hosting. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. The presence of external URIs and the PDF_RANDOM_URL_LINK heuristic point to the primary attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://irlanc.ru/uplcv?utm_term=sync+android+contacts+to+computer PDF link annotation
    • http://huabulaw.com/uploadpic/2021-9/file/2021092517295573499.pdfIn PDF document text
    • https://amgaa.org/temp/files/5316517174.pdfIn PDF document text
    • http://cl-pub.com/files/files/134461838.pdfIn PDF document text
    • https://kisikana.hr/userfiles/file/buzulap.pdfIn PDF document text
    • http://ambulatorioveterinariocigliano.com/userfiles/files/kisupanofali.pdfIn PDF document text
    • https://nistd.in/userfiles/file/kesoxagigisinutibewobopos.pdfIn PDF document text
    • https://franchisefarm.franchiseharbor.com/files/files/notiredujikipoborivat.pdfIn PDF document text
    • http://gewoongroen.eu/app/webroot/files/userfiles/files/zizaz.pdfIn PDF document text
    • https://sakesushimn.com/userfiles/files/94999746693.pdfIn PDF document text
    • https://interativacorretora.com/fotosempresa/files/mupunenujo.pdfIn PDF document text
    • https://www.pension-chevaux-haras-gabereau.fr/ckfinder/userfiles/files/pumukekeroritikelatiwege.pdfIn PDF document text
    • http://gruaszarate.com/ckfinder/userfiles/files/nivogonuxidap.pdfIn PDF document text
    • http://quangcaosms.org/media/ftp/file/xarisikusawoxug.pdfIn PDF document text
    • http://knipia.com/userfiles/file/77969671984.pdfIn PDF document text
    • https://www.supremecaravans.com.au/application/third_party/ckfinder/userfiles/files/90357205157.pdfIn PDF document text
    • http://ck-kutnahora.cz/gais/image/file/16357999539.pdfIn PDF document text
    • https://norservis.com/files/files/12840170879.pdfIn PDF document text
    • http://studiorinaldibedin.eu/userfiles/files/30860368168.pdfIn PDF document text
    • https://hsegroup.ru/wp-content/plugins/super-forms/uploads/php/files/lfm55libtvoodtoaghhdgim641/30378652050.pdfIn PDF document text
    • http://220-wm01.netdbhosting.com/file/ribuja.pdfIn PDF document text
    • https://gccpay.net/wp-content/plugins/super-forms/uploads/php/files/1ba1a4263012ea77961d886dbe0fa924/28403732616.pdfIn PDF document text
    • 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_off0000be56.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBE56 19356 bytes
SHA-256: 3b0379ffc1290d74f6b4be92d10fe4186c9741eb990cbcc385b3b1e0b452d26f
font_01_sfnt_off0000f114.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF114 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001092b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1092B 10916 bytes
SHA-256: 9a3e62f76635ee3d5302bce3dcd36e71dbebd9ac2e695d99447c375a81c7547e

Open this report in the interactive analyzer, or submit your own file for analysis.