Malicious PDF — malware analysis report

Static analysis result for SHA-256 2100af8f18d18721…

MALICIOUS

PDF

81.7 KB Created: 2021-03-11 15:40:49 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-21
MD5: 20a6d3a40d0bfd976becfb1186a5740e SHA-1: bd08cbce8ae44a18c30bb5c9989fb904aad5fdc2 SHA-256: 2100af8f18d18721a0f3b82de477d119a97e0e705567cdf02739238302841f3c
194 Risk Score

Malware Insights

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

The PDF document contains a large number of external links, many hosted on disposable domains, suggesting a link farm designed to redirect users. The document body, though heavily obfuscated, appears to be a lure related to software functionality, combined with metadata indicating it was generated by wkhtmltopdf. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to lead users to phishing or malware download sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 7

  • 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 contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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 https://ponafet.ru/strik?utm_term=how+to+activate+fuzzy+lookup+in+excel+2013 PDF link annotation
    • https://farazekij.weebly.com/uploads/1/3/4/3/134379469/077a522892a3160.pdfIn PDF document text
    • http://item-mask.top/we_vibe_promo_code_canadacs5tg.pdfIn PDF document text
    • https://zagefejov.weebly.com/uploads/1/3/2/7/132710748/6724595.pdfIn PDF document text
    • https://cdn.sqhk.co/metusoteliza/FFjdWeA/50080151222.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4374953/normal_5fe94bd76cf14.pdfIn PDF document text
    • https://cdn.sqhk.co/felolavap/YhecUN4/42466298269.pdfIn PDF document text
    • https://cdn.sqhk.co/lawikuto/DKjeljb/taradob.pdfIn PDF document text
    • https://cdn.sqhk.co/fogobewataja/iihirib/ube_crinkle_cookies_honolulu.pdfIn PDF document text
    • https://cdn.sqhk.co/xovujiroveg/fhfjd29/arp_guard_wifi_security_apk.pdfIn PDF document text
    • https://fezagigix.weebly.com/uploads/1/3/0/8/130813643/1511295.pdfIn PDF document text
    • https://cdn.sqhk.co/wovudojemu/jjgF2Gp/41705508693.pdfIn PDF document text
    • https://munuliwakubife.weebly.com/uploads/1/3/1/6/131637312/331992.pdfIn PDF document text
    • https://jadojojipolukot.weebly.com/uploads/1/3/5/3/135337887/2914bd20.pdfIn PDF document text
    • https://cdn.sqhk.co/mudaxomemut/Iibhe4B/kp_astrology_lessons_in_tamil.pdfIn PDF document text
    • https://sezifiloxoxo.weebly.com/uploads/1/3/5/3/135348424/kepusimovera-benilaf-rosuraku.pdfIn PDF document text
    • https://tarakemutelomul.weebly.com/uploads/1/3/2/3/132303353/a5b85f4c4b.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4412996/normal_5fff0aa06aa48.pdfIn PDF document text
    • https://cdn.sqhk.co/lemipetukaso/jt7c2GT/brother_hl-_l2321d_software.pdfIn PDF document text
    • https://cdn.sqhk.co/waxobakal/bjdihje/warcraft_lord_of_the_clans_game_download.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4416660/normal_5fdcb62beea0c.pdfIn PDF document text
    • http://cosmicgig.com/domunofrex4.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f25f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF25F 5504 bytes
SHA-256: e9ad2ff59faee59932821e39cab74db5676748d7cc838c09466ca8bcd564a1ef
font_01_sfnt_off0001055c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1055C 11140 bytes
SHA-256: 1f2d25aeb335e2a510e151c54ac96b7b6efec3d3d99a05c826c4420e57ea14df
font_02_sfnt_off00012b2c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12B2C 4324 bytes
SHA-256: 4fcfa7c68d76e23b667942a3ac892d2d5d88346478daafc61479ad4df4af3dd3