Malicious PDF — malware analysis report

Static analysis result for SHA-256 ca1f05b509c9271e…

MALICIOUS

PDF

77.5 KB Created: 2021-10-05 01:22:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: d63e37954faa0415bc3f636d30bbc05a SHA-1: 835b8ab472661f7c8549642cfbb5216375916346 SHA-256: ca1f05b509c9271e4569ea43318cf9f25b9dd387f728c2ab67cd86cc33e763d4
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The ML classifier and ClamAV detection strongly indicate maliciousness. The PDF contains numerous embedded URLs, many of which are hosted on suspicious domains and appear to be part of a link farm, suggesting an attempt to redirect users to malicious content. The presence of PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this. No scripts were extracted, but the overall structure points to a phishing or credential harvesting attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://thuonghieutoancau.vn/uploads/files/lidiwufadozar.pdf In PDF document text
    • http://tiszaladany.hu/upload/file/kedijuravurizesitiluzoz.pdfIn PDF document text
    • http://luyenthidhcanhsat.com/Images_upload/files/saxalebi.pdfIn PDF document text
    • https://jazykovytabor.topenglish.sk/app/webroot/gallery/files/13953163544.pdfIn PDF document text
    • https://gsacademy.ge/uploads/files/61359354571.pdfIn PDF document text
    • http://szkolka-wiercioch.pl/files/file/dugavevugarujisivap.pdfIn PDF document text
    • http://uralcomservis.ru/crn_fls/crn_files/wiwabamanotakutusevo.pdfIn PDF document text
    • http://dwallacelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/5116619228.pdfIn PDF document text
    • https://noble-worldwide.com/wp-content/plugins/super-forms/uploads/php/files/7d6e14e007a2f7c96c8721861f2fa9aa/55401231453.pdfIn PDF document text
    • http://abogadosaguilar.com/ckfinder/userfiles/files/63973556652.pdfIn PDF document text
    • https://franchise-vietnam.com/app/webroot/img/files/29803004223.pdfIn PDF document text
    • https://kamber.dk/wp-content/plugins/super-forms/uploads/php/files/dd45e6f299fc1c3bd885604dc33b5fb4/vilafitijeginesujife.pdfIn PDF document text
    • http://eco-building.cz/UserFiles/File/bukatosizizironafegukaful.pdfIn PDF document text
    • http://www.optimizecost.com/admin/ficheros_fckedit_subidos/pipezomipezajez.pdfIn PDF document text
    • https://samngaimarble.com/html_upload/file/degogakexatil.pdfIn PDF document text
    • http://www.tamtrebinhminh.com/public/files/jifutaxojusoxuvolaj.pdfIn PDF document text
    • https://bd-sokolovska.eu/userfiles/file/labubokemejifefa.pdfIn PDF document text
    • https://wct.goldcrownresort.com/magazine_files/files/laminuzowelamiw.pdfIn PDF document text
    • https://piataafacerilor.ro/app/webroot/files/userfiles/files/tavovubazubivova.pdfIn PDF document text
    • https://europawindow.com/app/webroot/img/main_content/files/88184446339.pdfIn PDF document text
    • http://www.vljainandco.com/userfiles/files/9432781482.pdfIn PDF document text
    • https://anitt.in/ckfinder/userfiles/files/jaworikizemefagijewi.pdfIn PDF document text
    • https://jhservice.net/imagenes/galeria/files/solinuridebuxo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=free+draw+online+multiplayerPDF 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_off0000c855.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC855 18388 bytes
SHA-256: 17598920209d7e37341add9b51ecfb20ac87ec833808a81c7d7cc3895b6affee
font_01_sfnt_off0000f8a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8A0 10660 bytes
SHA-256: 2434bdd1891f78f7450ed3df8e6a7c404444dc36092abb9835c74d34120b66a3
font_02_sfnt_off00011102.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11102 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1