Malicious PDF — malware analysis report

Static analysis result for SHA-256 56678b0596559492…

MALICIOUS

PDF

107.9 KB Created: 2021-04-25 11:33:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-25
MD5: c71771f465271459fc78ba7c175d1a10 SHA-1: d60e6711207f67f2b69f932e1a218cacce17b6e3 SHA-256: 56678b0596559492e8c03bc95111067235e91dc9e967f48714797a257812cf28
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many hosted on disposable domains, suggesting a link farm designed to redirect users to malicious sites. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were directly extracted, the PDF structure and embedded URLs point towards a phishing or malware distribution scheme, likely initiated via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • 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.
  • 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://dugedepap.ru/strik?utm_term=introduction+to+logic+and+critical+thinking+book+pdf PDF link annotation
    • https://rufuroborotefin.weebly.com/uploads/1/3/1/8/131856068/32713.pdfIn PDF document text
    • https://sadebisoj.weebly.com/uploads/1/3/2/3/132302749/492a59856.pdfIn PDF document text
    • http://niverokime.iblogger.org/daily_crossword_answers_mini.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
    • https://s3.amazonaws.com/rewepalazamiso/demolebatajulojanaret.pdfIn PDF document text
    • https://s3.amazonaws.com/devuxuzejozam/98403102631.pdfIn PDF document text
    • https://69c5641f-197a-42c1-bef1-daa502c1f1d7.filesusr.com/ugd/948cea_30668a60d94744b7b997654c0c251890.pdf?index=trueIn PDF document text
    • https://6f12065f-c45d-410c-b048-6ec23fb2b810.filesusr.com/ugd/02ccf7_bb29945a0e7b47e2bd4ed1268de40ae2.pdf?index=trueIn PDF document text
    • http://fepujusarif.epizy.com/teoria_del_aprendizaje_social_bandura.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/60b9e364-194c-419b-a19a-7a3f52089267/how_to_write_sql_query_in_dbeaver.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/311d69b4-3a97-47dc-8430-d099d32076eb/do_rational_functions_have_vertical_asymptotes.pdfIn PDF document text
    • https://ac614e2c-2e00-43e4-a80f-2c6bce9fb64b.filesusr.com/ugd/f103bb_3e7ef2f3e195452fa78f737581e2bece.pdf?index=trueIn PDF document text
    • https://0503187d-52cd-4237-9521-a3cb9bf551ae.filesusr.com/ugd/5bb01c_639e5c172a59429c86e0ea617d29c49f.pdf?index=trueIn PDF document text
    • https://dedb376b-efc3-4528-ac10-fc65d12f866c.filesusr.com/ugd/5f6074_46b1754ca33f4fcca3405016768fb41d.pdf?index=trueIn PDF document text
    • http://pugapugene.rf.gd/megekivepobofepogerofa.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1ad8dbb2-059f-4424-b524-095e48288978/26246220554.pdfIn PDF document text
    • https://6d251753-49d0-4f5b-a278-10ed1cacc9d0.filesusr.com/ugd/5c139a_b7c91d143c9345ec92bf889c2823e7b1.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/824fca44-457f-4f1b-a404-19c1b9b764ba/76762850210.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000159a1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x159A1 5144 bytes
SHA-256: 90df4e51963b20a88bc30ba643878a0877ff6ec0f48ac2a5cbb0f5e4c9ce0da6
font_01_sfnt_off00016b0b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16B0B 11444 bytes
SHA-256: 250df87e0ef20be8923a192b42c159cbe340d2a6970d99a5ad3bd39b9e1b0ae9
font_02_sfnt_off0001923d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1923D 4324 bytes
SHA-256: 7f6049e5011acf0e8581793f2bc2bb947aac2929fdb77abc318b2a6155c1ef71