Malicious PDF — malware analysis report

Static analysis result for SHA-256 36cb50a6c8c9d118…

MALICIOUS

PDF

81.8 KB Created: 2021-09-20 05:20:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 737468b7422bf43c422c028a3d00ddc4 SHA-1: 299cbfb31b57e39b82b2e78004c2f6dfe28ddd93 SHA-256: 36cb50a6c8c9d118296bc779a140ad7236de17ed73874d774d1ff3f57b887b67
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs that form a link farm, directing users to potentially malicious sites. Heuristics indicate these links are often hosted on compromised CMS uploads or disposable hosting, suggesting a phishing or malware distribution scheme. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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 https://huntic.ru/uplcv?utm_term=compound+angle+formula+proof PDF link annotation
    • https://tungafilm.com/dorceiys/ckfinder/userfiles/files/kefazewedivapu.pdfIn PDF document text
    • https://bibonatura.hu/ckfinder/userfiles/files/75702781501.pdfIn PDF document text
    • http://ingore.cn/upload/files/10041115165.pdfIn PDF document text
    • http://rc-saty.cz/gais/image/file/ropane.pdfIn PDF document text
    • http://baltic-rt.ru/ckfinder/userfiles/files/riretumugubunajafomedolem.pdfIn PDF document text
    • http://cheevalome.com/image/upload/File/xipegorufokitokoxel.pdfIn PDF document text
    • https://www.rath-catering.de/wp-content/plugins/formcraft/file-upload/server/content/files/1612fc350ee5c5---pakawowapilavodixaxux.pdfIn PDF document text
    • https://popa.com.br/wp-content/plugins/super-forms/uploads/php/files/baa3bf31cb4470b4a7d370107adcd3d2/jemot.pdfIn PDF document text
    • http://kapelski.pl/userfiles/file/16668071215.pdfIn PDF document text
    • http://itineraire-consulting.com/ckfinder/userfiles/files/95476935298.pdfIn PDF document text
    • https://cihangirhotel.com/upload/ckfinder/files/lesuwufasivulibowelim.pdfIn PDF document text
    • https://bodzlomu.com/userfiles/file/ketamodejevepozi.pdfIn PDF document text
    • https://ilonew.tasksplan.com/userfiles/files/newenawagafowukanil.pdfIn PDF document text
    • https://nakatarikaszel.pl/app/webroot/userfiles/file/24841977919.pdfIn PDF document text
    • http://tbvshungviet.com/upload/files/66552351307.pdfIn PDF document text
    • http://www.masozilina.sk/ckfinder/userfiles/files/92687437488.pdfIn PDF document text
    • http://premiumresourcing.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a94627356f---80406063965.pdfIn PDF document text
    • http://meetburgerusa.com/uploads/files/pawetidudukevavesuvabuj.pdfIn PDF document text
    • https://reazfarah.com/ckfinder/userfiles/files/pizusezaxonu.pdfIn PDF document text
    • http://faw-asia.com/image/upload/files/40960044354.pdfIn PDF document text
    • https://pluckywize.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ba43a45802---49281088821.pdfIn PDF document text
    • http://lncxjzxxw.com/upload_fck/file/2021-9-19/20210919123643333519.pdfIn PDF document text
    • http://jsqnchem.com/upload/files/96609783162.pdfIn PDF document text
    • http://fxlcd.com/upload/file/zinizubufuxubiruzakujepo.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_off0000d6ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6CE 10612 bytes
SHA-256: 6e19da36863b19f63b7518fa20432c04f00c8a7d283b6b5fe51f8e0a7fe45870
font_01_sfnt_off0000eece.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEECE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000106e0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106E0 19180 bytes
SHA-256: 1cb11af40c5dc9b84891cf6bbafe75220093f13ba48039c754ccb4be9fcfbf0f