Malicious PDF — malware analysis report

Static analysis result for SHA-256 87fff6483d7a509e…

MALICIOUS

PDF

78.9 KB Created: 2021-09-18 13:43:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 4977576e9fe26b3ae970d90eaa5c9b47 SHA-1: d5b30d39fe5be736c5442924f07e0f9256a6526a SHA-256: 87fff6483d7a509e9ea62fa2b4207f489a3d1653343a5f74b410c6a6814a7328
134 Risk Score

Malware Insights

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

The PDF contains numerous links to external resources, many of which are hosted on disposable domains, indicating a link farm designed to obscure the ultimate destination. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. The presence of a 'download button' heuristic further supports the lure-based attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://ocean-ex.com/images/blog/file/sowizukiru.pdf In PDF document text
    • http://www.hkimm.hk/_bin/ckfinder/userfiles/files/koxavokagi.pdfIn PDF document text
    • https://bunianco.com/other_files/File/tunupaxovuju.pdfIn PDF document text
    • http://pokwuttibut.com/file_media/file_image/file/gojobovipozemajavawawux.pdfIn PDF document text
    • http://scea.edu.mn/ckfinder/userfiles/files/63223093047.pdfIn PDF document text
    • http://sunnysolutions.it/uploads/assets/file/vufokirulofad.pdfIn PDF document text
    • http://unicorn-furnitures.com/d/files/83603207879.pdfIn PDF document text
    • https://nepalmicrofinancesummit.org/userfiles/files/41392174402.pdfIn PDF document text
    • http://dichvutot99.com/webroot/img/files/wuxogiwonib.pdfIn PDF document text
    • https://millersexpress.com/userfiles/file/57723430862.pdfIn PDF document text
    • http://sambometal.com/dataroom/file/puregefojo.pdfIn PDF document text
    • https://sarna-zapiekanki.pl/ckfinder/userfiles/files/wowiselajazutuliragim.pdfIn PDF document text
    • https://plumcourse.com/wp-content/plugins/super-forms/uploads/php/files/01ac22933a9ddd09d429df34e268b937/beribelez.pdfIn PDF document text
    • http://haiannweb.com/uploads/files/bidolaxiveledupubavo.pdfIn PDF document text
    • http://designpavelzapletal.cz/files/file/19674541182.pdfIn PDF document text
    • https://lean-ds.com/upload/editor/file/gizarisikudebukitoxana.pdfIn PDF document text
    • https://vietnamwelder.vn/uploads/news_file/memuveroxazufigu.pdfIn PDF document text
    • http://daiichigroup.net/uploads/news_file/lavikopevutema.pdfIn PDF document text
    • http://jerseybankruptcylaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/69851242234.pdfIn PDF document text
    • http://2sisaccount.com/userfiles/files/nabolewaze.pdfIn PDF document text
    • http://mousike.it/img_ins/files/60331231758.pdfIn PDF document text
    • http://www.terresdescaraibes.fr/file/51081480792.pdfIn PDF document text
    • http://khunghinhdepphuctin.com/media/ftp/file/torugakiwuv.pdfIn PDF document text
    • http://gptools.net/userfiles/file/lazarelorilafeperifarawa.pdfIn PDF document text
    • https://eownauto.com/uploadpic/files/xufunelu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=latest+mod+appsPDF 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_off0000d0e9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD0E9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e900.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE900 10168 bytes
SHA-256: e363971aa50f26e68735c4b14a7c4d0d84a9be689b58692146677c984e364f19
font_02_sfnt_off0000ffca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFCA 17732 bytes
SHA-256: a6367c3d722f1dbb9fc0519837b1d54939011a26118e900855baca252f19aee3