Malicious PDF — malware analysis report

Static analysis result for SHA-256 6cd8db4ecb28df4a…

MALICIOUS

PDF

79.6 KB Created: 2021-05-15 08:51:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-21
MD5: ca751013461d40576527b9c16fb197a9 SHA-1: c8efc66aff856aca048c52863934c5603df98b50 SHA-256: 6cd8db4ecb28df4ae0edd89a0a0784b80674a2d51da8ee6559b992e710138456
244 Risk Score

Malware Insights

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

The PDF contains numerous embedded links, many pointing to disposable hosting services, indicating a link farm or phishing attempt. Heuristics confirm the presence of malicious redirector links and a large number of external PDF links. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or SEO spam.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 6

  • 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.
  • 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://crophysi.ru/strik?utm_term=historical+development+of+the+concept+of+life+pdf In PDF document text
    • https://zosetujisux.weebly.com/uploads/1/3/4/2/134266291/moxozun.pdfIn PDF document text
    • https://tukumexof.weebly.com/uploads/1/3/4/7/134721389/xovidoni_kerudetowew.pdfIn PDF document text
    • https://fumunavizagoz.weebly.com/uploads/1/3/4/2/134235019/poledevelasak.pdfIn PDF document text
    • https://kuxesilivalagi.weebly.com/uploads/1/3/5/9/135963561/6656505.pdfIn PDF document text
    • https://bovimifukid.weebly.com/uploads/1/3/4/8/134882826/f8a2be2ecf7c2.pdfIn PDF document text
    • http://zugapuvu.mywebcommunity.org/how_to_avoid_pattern_day_trader_rule_robinhood.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4477877/normal_5fffff2495d85.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4408462/normal_5fe8488dbc14f.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4410194/normal_5fe79928891ae.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4408712/normal_605258e4f261b.pdfIn PDF document text
    • https://gazasajud.weebly.com/uploads/1/3/4/8/134879445/gumoduvozeninorazid.pdfIn PDF document text
    • https://suwudaxodorepe.weebly.com/uploads/1/3/4/8/134885248/javosutuduwi.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4404953/normal_600cef4e7983d.pdfIn PDF document text
    • https://duvokazi.weebly.com/uploads/1/3/4/1/134108747/1957931.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/fedure/79078341775.pdfIn PDF document text
    • https://0404cab7-c021-4537-be79-420bcb2f88cc.filesusr.com/ugd/52c240_6f9ac99863d74a11b0a81b87325241fa.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/dubiditiginowo/restaurant_honfleur_guide_michelin_2017.pdfIn PDF document text
    • https://s3.amazonaws.com/datarofapakil/44547343545.pdfIn PDF document text
    • https://s3.amazonaws.com/nuselufuzo/n_h_letter_whatsapp_status_video.pdfIn PDF document text
    • http://zijiwaras.onlinewebshop.net/aptitude_test_questions_and_answers_infosys.pdfIn PDF document text
    • https://4eff3ec4-d147-45d1-be73-876d9e1d0019.filesusr.com/ugd/efb3f0_ec8ff56547f347d58e22f678d7014231.pdf?index=trueIn PDF document text
    • https://1c92f6d8-19eb-429c-9239-1cf6be91372f.filesusr.com/ugd/cc1a03_51fddd39ccaa4533b51bdc073d87b146.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_off0000f84a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF84A 5416 bytes
SHA-256: f14a6c004ac560ae9b8056bcbb47f49ade68bba85fee36d81a4e535cc317eeb6
font_01_sfnt_off00010a90.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A90 10652 bytes
SHA-256: 5687246a49474e26213e7c7aaa9d70f68179d38e3a9caa2292c0a72a9cfa1932