Malicious PDF — malware analysis report

Static analysis result for SHA-256 dfc329b1c4adc210…

MALICIOUS

PDF

75.6 KB Created: 2021-09-19 12:21:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 073b5274e19312bc532c803b79552ff2 SHA-1: e2efc528d0a7fef19b39141627a94200129fa244 SHA-256: dfc329b1c4adc210afd3b5f55e7ccbbae1ba234c22498be4ae85ff0d057e3d70
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The ML classifier and ClamAV detection strongly indicate malicious intent. The PDF contains numerous embedded URLs, many pointing to disposable domains, suggesting a link farm or phishing lure. The presence of PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating a tactic to obscure the true destination or spread malicious links across many domains. No scripts were extracted, but the overall structure and heuristic firings point to a malicious PDF designed to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9827

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 https://www.kindspring.org/inc/ckfinder/userfiles/files/nipenobasojomesiv.pdf In PDF document text
    • http://appartementslisa.it/an3_Uploads/file/xukijumif.pdfIn PDF document text
    • https://groupekheidri.com/ckfinder/userfiles/files/jipimigixoxuj.pdfIn PDF document text
    • https://yuanfuconstruction.com/ckfinder/upload/files/54496929173.pdfIn PDF document text
    • http://imbirimbir.ru/files/fiwebidesomuvakavajez.pdfIn PDF document text
    • http://kwik-it.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16138917cc6f81---jikanadupiki.pdfIn PDF document text
    • https://thanaclusterwestgate.leaddeehub.com/userfiles/files/gafifoduri.pdfIn PDF document text
    • https://parlagame.net/calisma2/files/uploads/62118724596.pdfIn PDF document text
    • https://jxlmedu.com/file/files/20210914_175652.pdfIn PDF document text
    • https://nhaban24h.com.vn/wp-content/plugins/super-forms/uploads/php/files/ud5s0dq5pc4p0tps0oo9f7m2ss/90817596217.pdfIn PDF document text
    • http://anindecor.pl/files/file/dudulajosa.pdfIn PDF document text
    • http://sun-eko.eu/files/file/mavizozomasujenivateji.pdfIn PDF document text
    • http://phyllisrubensteinlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/23345102513.pdfIn PDF document text
    • http://cherriestattoo.com/ckfinder/userfiles/files/xopelizexexabefigabip.pdfIn PDF document text
    • https://alpasol.e-giant.net/upload/files/pexan.pdfIn PDF document text
    • https://www.ojchamber.com/ckfinder/userfiles/files/kepigugofig.pdfIn PDF document text
    • https://www.utn.ac.cr/sites/default/files/files/gefewiminuvododirugem.pdfIn PDF document text
    • http://hillsdalehorseboarding.com/ckfinder/userfiles/files/61240425381.pdfIn PDF document text
    • https://1877painters.com/FCKeditor/file/43192235987.pdfIn PDF document text
    • http://pune-india.info/userfiles/file/66593667339.pdfIn PDF document text
    • http://yas-center.ru/userfiles/file/megesugekitepunof.pdfIn PDF document text
    • http://fukaofoods.tw/uploads/files/202109081313084847.pdfIn PDF document text
    • http://7seapharmtech.com/Uploadfiles/files/takefomawi.pdfIn PDF document text
    • http://quartierdete.fr/uploads/fckeditor/file/37771316990.pdfIn PDF document text
    • http://goldendazzle.com/upload/quangtri/files/bularadoromijujenexigan.pdfIn PDF document text
    • http://alibabashipping.com/userfiles/file/70349029657.pdfIn PDF document text
    • https://tefen67.com/userfiles/files/sasigiworuvub.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=cast+my+phone+on+laptopPDF 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_off0000c26c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC26C 17884 bytes
SHA-256: eded0cf321b6330a07d9145485f36c0ed73d093a38912d7c88dd6b4408f101fd
font_01_sfnt_off0000f0ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0FF 10472 bytes
SHA-256: d5c3e061786622c47a4a2e255e602da7c3f8aa227bae13aa6744afd57981ec14
font_02_sfnt_off000108a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108A7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1