Malicious PDF — malware analysis report

Static analysis result for SHA-256 c819fcaac37e28b1…

MALICIOUS

PDF

82.0 KB Created: 2021-03-19 08:46:43 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-21
MD5: 9bc06d6691901fb651cbcd65f835b6c4 SHA-1: 25c393f731131f1a0171ca217ab9c80026607218 SHA-256: c819fcaac37e28b19d7be226f5b2c5e4f1da9408aa88caa2f8dfeb4ff9768e0a
244 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links, many pointing to disposable hosting, indicating a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution via these links. While no scripts were directly extracted, the PDF structure and embedded URLs are indicative of a malicious redirection scheme.

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/award?keyword=computer+aided+engineering+drawing+pdf In PDF document text
    • https://cdn.sqhk.co/zalivelo/iK11hdB/games_cheat_codes_for_pc.pdfIn PDF document text
    • https://cdn.sqhk.co/todusukiraxi/Mjegdic/candy_frenzy_free_download.pdfIn PDF document text
    • http://bulepozobagepud.mygamesonline.org/arcadismo_exercicios.pdfIn PDF document text
    • https://xududegugi.weebly.com/uploads/1/3/1/6/131636960/1804785.pdfIn PDF document text
    • https://kuxijixa.weebly.com/uploads/1/3/4/8/134856984/vadavis.pdfIn PDF document text
    • https://cdn.sqhk.co/ratufewebu/jkgidgf/primal_legends_download_pc.pdfIn PDF document text
    • http://pegijegur.mygamesonline.org/d15sb80_bridge_rectifier.pdfIn PDF document text
    • https://wajefoxefibivi.weebly.com/uploads/1/3/2/8/132814680/415098.pdfIn PDF document text
    • https://rufudejipuxege.weebly.com/uploads/1/3/5/3/135347647/b0aa4.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
    • http://regujivabi.rf.gd/nelonitekojakifaleb.pdfIn PDF document text
    • https://s3.amazonaws.com/suzujewa/pawijisofidexo.pdfIn PDF document text
    • http://jelirasu.rf.gd/bayesian_statistics_course_mit.pdfIn PDF document text
    • http://murapimopavopa.myartsonline.com/jenegipanugulodo.pdfIn PDF document text
    • https://0ea1ff7f-05b3-43a2-9744-178351a05ed1.filesusr.com/ugd/01f9b9_411ccf79106b4b12b2ca17ca6e0c2c65.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/godewumazek/nibigexexolorosidode.pdfIn PDF document text
    • https://s3.amazonaws.com/remufuzu/movie_website_for_pc.pdfIn PDF document text
    • https://s3.amazonaws.com/juzinaramip/tusilirulupekatitodusaxa.pdfIn PDF document text
    • https://34ec465e-51aa-4dba-9a8c-c05fcfb5ae84.filesusr.com/ugd/df15ee_46ab4980d10247c3885df8307ac4182a.pdf?index=trueIn PDF document text
    • https://a3de454e-1598-42bb-a259-4eb69c42f179.filesusr.com/ugd/fb5067_248b2710e03440059105751098fe2b00.pdf?index=trueIn PDF document text
    • https://61249681-e2d1-4375-841a-b3723294d79c.filesusr.com/ugd/3d514e_dae904950563400e9a82e3ac0281428a.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f692.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF692 5148 bytes
SHA-256: 27cfec144972fe8aa1c4a789871558b00a8c51d27b85f5ac83df118ac1c599d5
font_01_sfnt_off00010814.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10814 10984 bytes
SHA-256: 9af8be5e971be3ddbfe8cda9498c1bc4d860668b1ac971aa20d29720d83777a0
font_02_sfnt_off00012d47.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D47 4324 bytes
SHA-256: d1f4a20f0e35a0564be54678b929bb8c711862c507f070c2b9a6abea8daf4378