Malicious PDF — malware analysis report

Static analysis result for SHA-256 bbd9a4e339ad4225…

MALICIOUS

PDF

71.9 KB Created: 2021-04-02 10:41:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-02
MD5: 159032dbb4957b0d99a222bd4c73aef3 SHA-1: eb82e89fc3366fbb092b78108f8d13d6d5cc73b6 SHA-256: bbd9a4e339ad4225d7404731d7d98a28b2c40aee8abbdb2c643af098f04a963b
184 Risk Score

Malware Insights

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

This PDF file was identified as malicious by multiple heuristics, including a critical finding for a link to known malicious redirector infrastructure. The embedded URL `https://crophysi.ru/strik?utm_term=aa+steps+workbook+pdf` is the primary indicator of malicious intent, likely serving as a lure to a phishing or malware distribution site. The document's structure and numerous embedded links suggest it is part of a link farm designed to obscure the final malicious destination.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

Heuristics 5

  • 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 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=aa+steps+workbook+pdf In PDF document text
    • https://judenebubiz.weebly.com/uploads/1/3/4/6/134656374/3195941.pdfIn PDF document text
    • https://wumotobu.weebly.com/uploads/1/3/4/3/134370577/59839.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4465548/normal_60521bbe035ce.pdfIn PDF document text
    • https://naxibozagut.weebly.com/uploads/1/3/4/5/134580084/dekujanaliko.pdfIn PDF document text
    • https://koxepaje.weebly.com/uploads/1/3/5/3/135350813/795f1f07b7.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4473388/normal_601b66109c49b.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4443624/normal_5fe23a868a1da.pdfIn PDF document text
    • https://putumilaw.weebly.com/uploads/1/3/1/3/131380263/566d518.pdfIn PDF document text
    • https://bijejumutitin.weebly.com/uploads/1/3/1/4/131454352/4493735.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4381344/normal_5fdd92bbdb656.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4411916/normal_604ce85c525df.pdfIn PDF document text
    • https://bifixebuwo.weebly.com/uploads/1/3/0/7/130776276/3585594.pdfIn PDF document text
    • https://menerixejujup.weebly.com/uploads/1/3/4/6/134605313/859674.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/cb2da8cd-9d22-4f12-bce9-7328f0e72fe2/57127164206.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b145c0f6-9348-48f2-926b-52f26e5bfc82/jibugomadofikujimom.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/96062c34-1519-47cb-9aa1-fa5ff1cb1722/59760819335.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7a7c7db2-ad5a-4464-a8a2-c9ec035f59b0/god_of_small_things_chapter_12_summary.pdfIn PDF document text
    • http://jijitereni.rf.gd/84195991692.pdfIn PDF document text
    • http://sipifubovok.epizy.com/les_accents_cours.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e9f35018-3456-400e-9cf1-16947e5ed0f4/how_do_you_say_common_phrases_in_italian.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/06b7f45c-4545-4e41-b644-c63cec26b886/how_much_is_medical_laboratory_technology_salary.pdfIn PDF document text
    • http://zalufebali.rf.gd/animal_adaptations_worksheets.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/080ebe73-deda-46c9-8702-94c9c13af345/75158514842.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_off0000dbb4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBB4 5288 bytes
SHA-256: bce760a754a2aa88c9fafa5b2ca6a1a9e12835c3a46a356b2dd6ae49cd5dde77
font_01_sfnt_off0000edd4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDD4 10716 bytes
SHA-256: f513445785866b87b862a2b096ad296293f425a9c42ea9b9efb1bdc42185bbce