Malicious PDF — malware analysis report

Static analysis result for SHA-256 419f93c204dc2314…

MALICIOUS

PDF

79.4 KB Created: 2021-03-06 01:16:06 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-22
MD5: d8c41c55b81534a9bd0aff688897b515 SHA-1: 4f9820204d2104da206eaab46c1c1fe8f5c6817b SHA-256: 419f93c204dc23149829ea5c371d5f298e3a7e9fdfa45adf3a10a53fc0fa4b7b
284 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript T1203 Exploitation for Client Execution

The PDF file contains a high number of embedded links, many pointing to disposable hosting, and one critical heuristic indicates it links to known malicious redirector infrastructure. The presence of a fake CAPTCHA heuristic suggests a social engineering tactic to trick users into interacting with these links. The ML classifier also flagged this PDF with high confidence, and ClamAV detected it as a phishing trojan.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • Fake CAPTCHA / human verification prompt high SE_FAKE_CAPTCHA
    Document displays a fake CAPTCHA or human-verification prompt — used to trick users into running commands or pressing keyboard shortcuts
  • 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.
  • 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://dafemum.ru/award?keyword=how+do+i+log+into+my+facebook+business+page+without+a+personal+account In PDF document text
    • https://tuzuxomewe.weebly.com/uploads/1/3/4/5/134527180/matawupa.pdfIn PDF document text
    • https://cdn.sqhk.co/zexukobesu/SQZicSX/simaxarenovofev.pdfIn PDF document text
    • https://cdn.sqhk.co/lolumebitana/bqgcSt6/rebuilding_together_pittsburgh.pdfIn PDF document text
    • https://cdn.sqhk.co/fagaluwozez/hcRflhc/fosozobododufi.pdfIn PDF document text
    • https://tunimesepet.weebly.com/uploads/1/3/1/4/131455680/babagev.pdfIn PDF document text
    • https://zuzuxaze.weebly.com/uploads/1/3/4/0/134040629/4316b00.pdfIn PDF document text
    • https://cdn.sqhk.co/mujekesire/3dgiokl/43330566900.pdfIn PDF document text
    • https://cdn.sqhk.co/lenufetimop/X7Z5jbr/woworozizo.pdfIn PDF document text
    • https://cdn.sqhk.co/lamajemomu/jcibgiI/frontal_gaming_shop_diamond_ff.pdfIn PDF document text
    • https://cdn.sqhk.co/soxuxopova/ibiFibu/22008034089.pdfIn PDF document text
    • https://cdn.sqhk.co/semiwewedazi/gbijahe/25050020613.pdfIn PDF document text
    • https://gepufefodu.weebly.com/uploads/1/3/4/0/134013389/welek_sibigodiza_munes.pdfIn PDF document text
    • https://maparezoja.weebly.com/uploads/1/3/5/3/135321508/welatexox_wuvinaxagiz_tulabu.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://b5c90759-dbf8-4ccd-b12d-e23c958527f9.filesusr.com/ugd/915a55_ffcbea92f992484a9cebcb3e8c536b51.pdf?index=trueIn PDF document text
    • https://d89a15f7-21b5-45f0-b9b4-bc5b7be68842.filesusr.com/ugd/18e821_854368fdf33249a882d24c94ff92d238.pdf?index=trueIn PDF document text
    • https://73a1781f-5c9f-4c76-8a11-a8e8c44f336a.filesusr.com/ugd/d9f7b5_e22d06927f0a44368955d87b570452d0.pdf?index=trueIn PDF document text
    • https://48e6b720-b653-4920-beb0-7ef171ab6ab9.filesusr.com/ugd/d9d1f5_7449db55205f4e35b40fc9b758a73ecf.pdf?index=trueIn PDF document text
    • https://5663e088-3595-439c-971a-5873693bee35.filesusr.com/ugd/e98895_71c645a7841c4bd898801b47726e7519.pdf?index=trueIn 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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f80f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF80F 5928 bytes
SHA-256: a467438e7b668d58c07291ce5cb7265100c978debbcf08f775076efdfe2bd418
font_01_sfnt_off00010c2a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C2A 10300 bytes
SHA-256: 1a545d910fe21b169700dcb262bb979cd398283927cb20953d89c05ff7551f68