Malicious PDF — malware analysis report

Static analysis result for SHA-256 c83242303dd7df58…

MALICIOUS

PDF

84.5 KB Created: 2021-09-06 15:34:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: ccd9c086da15710194093effe66248d6 SHA-1: 08fe8df29b6831668b9774a91afad3a6e64433ec SHA-256: c83242303dd7df5808e07e29d61964d57ba90dac964741a9061cda8c088e9dd0
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, with numerous embedded URLs pointing to potentially compromised websites or disposable hosting. The document body is heavily obfuscated, but the presence of many external links suggests a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://studiodugnani.it/userfiles/files/fuzudipusamaf.pdf In PDF document text
    • http://atomleasing.ru/media/File/betiridab.pdfIn PDF document text
    • http://parbatsamajjapan.com/img/files/files/29158507569.pdfIn PDF document text
    • https://aristi-trap.com/upload/users/files/zubak.pdfIn PDF document text
    • http://uralinteh.com/uploads/files/dixawix.pdfIn PDF document text
    • https://kidneystonetreatment.in/userfiles/files/sejepatif.pdfIn PDF document text
    • http://www.nbc.com.vn/ckfinder/userfiles/files/73712444488.pdfIn PDF document text
    • https://soba05.org/wp-content/plugins/super-forms/uploads/php/files/f88ab370cf84c74034edc2317cc55043/seserokexuwejoxizuvug.pdfIn PDF document text
    • https://n95america.com/wp-content/plugins/super-forms/uploads/php/files/da28c95bde2876eb4ff1e87a9be13d99/bizitujezuvudi.pdfIn PDF document text
    • https://editionsitaliques.com/userfiles/file/2786345110.pdfIn PDF document text
    • http://nek.ua/wp-content/plugins/formcraft/file-upload/server/content/files/1609c164b511cc---limelatajupa.pdfIn PDF document text
    • http://sanitaerprofi.ch/fckeditor/editor/images/file/4339743312.pdfIn PDF document text
    • https://cebrigantina.com/025-CEB/images-editor/file/49165317922.pdfIn PDF document text
    • https://hijaustabilo.com/contents//files/nugilaturuzubava.pdfIn PDF document text
    • https://alice-immo.com/userfiles/file/vokitaba.pdfIn PDF document text
    • https://highendteen.com/userfiles/files/82294473202.pdfIn PDF document text
    • https://www.domosystem.gr/ckfinder/userfiles/files/depobowiwila.pdfIn PDF document text
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/78eb68ad3676011c2c3bb162916b18ea/lugirijibasupejatama.pdfIn PDF document text
    • http://xn--80aafbanafwvcftiqfecrg2a.xn--p1ai/pict/file/zonubesidagixomigetos.pdfIn PDF document text
    • https://nationalcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ea2de17df9---97867589269.pdfIn PDF document text
    • https://marksiegeldds.com/wp-content/plugins/super-forms/uploads/php/files/6cc7843fc2fce7ccad0bfce7e6d85bbf/95146958697.pdfIn PDF document text
    • https://bomberosdenavarra.com/userfiles_nexo/files/86651883827.pdfIn PDF document text
    • http://ongxoanhdpe.vn/upload/files/42979330593.pdfIn PDF document text
    • https://francois-daulte.com/ckfinder/userfiles/files/30822317556.pdfIn PDF document text
    • http://pension-erlkoenig.de/img/editor/file/pilopalutivi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=revista+minha+natura+ciclo+9+2018+pdfPDF 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_off0000d746.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD746 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ef58.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF58 21624 bytes
SHA-256: 29f2832655a2db02fb4d4ff3305bb61695d7ab0de0650d607a3cde41d50ef9b7
font_02_sfnt_off0001269a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1269A 11764 bytes
SHA-256: 8233fa1422b7f9a16904384aa08ea0893dc6ef21b3b5b9b3eb32179133b09db8