Malicious PDF — malware analysis report

Static analysis result for SHA-256 ca8d0bff3a635ed6…

MALICIOUS

PDF

71.6 KB Created: 2021-04-12 19:43:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-02
MD5: d4c1d934aa8612b5ddfdad948b145472 SHA-1: 2d99aed93fe1487f477a3d93fd489af733f08b93 SHA-256: ca8d0bff3a635ed6528e9ae1a63575626dfb48a020757780750c2c36528cd526
246 Risk Score

Malware Insights

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

This PDF document contains numerous external links, many pointing to disposable domains, suggesting a link farm or phishing lure. The presence of a callback phishing lure heuristic indicates an attempt to trick users into calling a fraudulent support number. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to redirect users to malicious sites for credential harvesting or further payload delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 8

  • 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.
  • Image-heavy PDF with invisible link to suspicious domain high PDF_SUSPICIOUS_LINK_LURE
    PDF is a small image-heavy lure with invisible link annotations that send the user to a suspicious high-risk-domain URI. This matches credential-phishing carriers where the visible document is only a prompt and the real collection flow happens on the linked website.
  • 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • 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://midufefew.ru/strik?utm_term=armitron+45%252F7042+hourly+chime PDF link annotation
    • http://com-login8.xyz/parrot_mki9200_remote_does_not_workg2o2f.pdfIn PDF document text
    • https://cdn.sqhk.co/gujowaxexag/gjjQjf4/2030623402.pdfIn PDF document text
    • http://kkkirrreeee.space/principles_of_realism_in_education7dhf3.pdfIn PDF document text
    • http://qupieasy.online/hush_hush_series_book_395y8p.pdfIn PDF document text
    • https://cdn.sqhk.co/tonukabonuwe/Wvbijjb/86585581561.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4447914/normal_60622db944eb2.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4376371/normal_5ff666d82eb3d.pdfIn PDF document text
    • https://cdn.sqhk.co/gugapedulob/fjj4djc/82633246166.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4390055/normal_5ffb63b276035.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/d77f2100-95c2-458d-a388-7c6c2fb0f5ed/47470274691.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/14531483-571a-4340-aa5a-39c2138807b3/2012_chevy_equinox_engine_replacement_cost.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f616d4b3-aa13-4a97-983e-4b5ae233338c/likujatodi.pdfIn PDF document text
    • https://71b4061d-0fbe-47a8-a671-08758978b022.filesusr.com/ugd/0216f2_4da600ee973f40b08656eaef7f1c249e.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/a70a5057-5ef1-46c0-94ad-66e9aab6e66f/how_to_connect_altec_lansing_speakers_together.pdfIn PDF document text
    • https://fb075467-9d00-46c6-93ac-2b777f5e584b.filesusr.com/ugd/8bcd66_397da6c8ebc34811b70acc3c62c50ef5.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/c10016f7-3233-42cf-b92c-f0eb0cce9833/vivitar_283_manual.pdfIn 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_off0000db00.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB00 5344 bytes
SHA-256: 6f80d14d886fe17a125c7a451d0b992c35bd99e4cdaa202b25d491cf922303d1
font_01_sfnt_off0000ed2d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED2D 10760 bytes
SHA-256: 000a060a04e4db45a16fb0784b415f5814c515fad46595a0245a41b2d9e8cac6