Malicious PDF — malware analysis report

Static analysis result for SHA-256 b596b1b67c632bd4…

MALICIOUS

PDF

81.4 KB Created: 2021-03-26 06:39:32 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-25
MD5: fe3f41c8f8ce5ae98fe3a248ddc85fda SHA-1: de755fac43f79d5ccbc8c120ab5a18e94a01f511 SHA-256: b596b1b67c632bd4afe328ba51d57f63f814b9bdcde7c73d629376ad62edc9c0
186 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many hosted on disposable domains, suggesting a link farm or SEO spamming operation. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and heuristic firings point towards techniques used to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://midufefew.ru/wix?keyword=65+cooking+terms+word+search+answer+key PDF link annotation
    • https://cdn.sqhk.co/vedoreket/hhibxij/magasenowali.pdfIn PDF document text
    • https://xunumiselodaz.weebly.com/uploads/1/3/0/7/130775676/weforafeberowibukuw.pdfIn PDF document text
    • https://butiziro.weebly.com/uploads/1/3/4/3/134308177/binigawitipinek.pdfIn PDF document text
    • https://janodiwuzujemux.weebly.com/uploads/1/3/1/3/131382133/2d4f3d4e.pdfIn PDF document text
    • https://pofitokibifezaf.weebly.com/uploads/1/3/5/3/135394855/gomutan.pdfIn PDF document text
    • https://zanazajerepa.weebly.com/uploads/1/3/4/0/134012527/mekabufafuf_vimusutifoje_gubowopotalu.pdfIn PDF document text
    • https://tifixexeruwa.weebly.com/uploads/1/3/2/6/132682204/duzepureru_fevowogogopize_xofopi.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4413474/normal_6044590c4ed6d.pdfIn PDF document text
    • https://cdn.sqhk.co/wojusipi/gfOjdCZ/97015713775.pdfIn PDF document text
    • https://cdn.sqhk.co/zaliroded/yhghiie/javuvupovirozas.pdfIn PDF document text
    • https://cdn.sqhk.co/fivuwunar/HEifWlQ/21931774237.pdfIn PDF document text
    • https://kunobozawi.weebly.com/uploads/1/3/1/4/131453145/vetituluzoda-vubul.pdfIn PDF document text
    • https://cdn.sqhk.co/remimidotomi/iiKLO0J/posejebo.pdfIn PDF document text
    • https://topizamo.weebly.com/uploads/1/3/4/4/134435864/tugifasuv_podonegif.pdfIn PDF document text
    • https://lojapajarete.weebly.com/uploads/1/3/4/5/134521209/juvuvose.pdfIn PDF document text
    • https://wokoxulepimam.weebly.com/uploads/1/3/1/4/131438011/mivikasowokulot-kabofamo-mupogotasumudu.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4463287/normal_604f84e916934.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4422371/normal_6022eacfc8035.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4457279/normal_60480175e1a75.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://38f9ccf9-db33-4582-994d-0ea518e52d38.filesusr.com/ugd/368de4_3c3c686a999b454393ce92826baabab8.pdf?index=trueIn PDF document text
    • https://3857ddc0-2b33-46ba-b4a8-ebef9b167687.filesusr.com/ugd/5cc0d5_f707ab20439340c4b78a84abfb9ac25d.pdf?index=trueIn PDF document text
    • https://8f20b4bd-83f7-4a55-8c6f-e9501e2e061c.filesusr.com/ugd/c1c462_6a0433c6d50645d4a74f3970527082e2.pdf?index=trueIn PDF document text
    • https://b2fc43c4-60ab-4dc1-a1c8-84833fda4e2a.filesusr.com/ugd/37321e_71729b10928246bfbc0568ecd5569f7c.pdf?index=trueIn PDF document text
    • https://d497f082-4895-42de-a72c-038d9367c8a3.filesusr.com/ugd/8e727b_97cccc83501f42f680d54a6552f04785.pdf?index=trueIn PDF document text
    • https://ec2d952e-5494-46d8-b841-fee222248b17.filesusr.com/ugd/9713d5_55b90bfd3f364ef8bc97f341fb43109a.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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e0b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0B0 5764 bytes
SHA-256: f719a7fe2d5171a2646308b10be583900e8f382a8d624c72320c5972143c61b1
font_01_sfnt_off0000f449.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF449 11268 bytes
SHA-256: 70efd31a1a7198193d459888da2d4fa3ef60eb87bcbefab6b98b3ca2941f5c27
font_02_sfnt_off00011a62.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A62 18736 bytes
SHA-256: cc16e10bbc7d09862ce082056afbc971b4356baa29bc41554c03fd6c78527fe7