Malicious PDF — malware analysis report

Static analysis result for SHA-256 c36bd3a068c75666…

MALICIOUS

PDF

98.5 KB Created: 2021-03-08 16:56:44 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-22
MD5: 2d5150245065ecd94ef7440d33f838e9 SHA-1: d806391b6985778ef17a48eea75746372ce0f154 SHA-256: c36bd3a068c75666fb61931e170b021661279bbbc4515bd720dca2a546813b76
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 of which point to disposable hosting, indicating a link farm or SEO spam operation. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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
  • 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://golowaki.ru/strik?utm_term=que+es+un+titulo+de+credito+hipotecario+negociable+peru PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4371020/normal_5fd72ae215f69.pdfIn PDF document text
    • https://rokopopowatapo.weebly.com/uploads/1/3/0/9/130969888/8220812.pdfIn PDF document text
    • http://luxomozuk.mypressonline.com/find_the_size_of_each_exterior_angle_of_a_regular_polygon_with_24_sides.pdfIn PDF document text
    • https://fiwaluveniwob.weebly.com/uploads/1/3/5/3/135395264/3079670.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4453906/normal_603bc342f1b87.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4412164/normal_6031de8a561af.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4410459/normal_6045f24690b35.pdfIn PDF document text
    • https://guravigipide.weebly.com/uploads/1/3/2/8/132815190/9381845.pdfIn PDF document text
    • https://zuvitapud.weebly.com/uploads/1/3/1/4/131406427/ginisivum.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4450635/normal_6011e95379b88.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://ebc1add8-0b9d-418e-9e4a-1e287827e933.filesusr.com/ugd/ab63e3_6607e3a2c415473190721ffc652ab265.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/jenagubadopi/nigiruzowevoxiwirupewo.pdfIn PDF document text
    • https://98be45bc-63b9-4117-aff7-84a3d4f2c4a0.filesusr.com/ugd/90c678_d35b5f2a023f436894e343ca62f79b44.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/voropa/13074151492.pdfIn PDF document text
    • http://fijorolur.myartsonline.com/satazeputifofugekijil.pdfIn PDF document text
    • https://a21f0d7d-5fe0-4a99-a381-3b18266e0880.filesusr.com/ugd/6c313a_ff8dd5f8a9ac4749a249c49a29551ebf.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/nevowimo/xixaxuduliretogobelol.pdfIn PDF document text
    • https://s3.amazonaws.com/pasawexawinogad/34702288125.pdfIn PDF document text
    • https://ecfc1f44-6648-4072-bff5-6ee4adcfbe4f.filesusr.com/ugd/e5a943_8873124b3bfd4434be4a91f52432bd93.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_off000140b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x140B6 5536 bytes
SHA-256: a3438df52c7c5379c4103c208823e02921c6c84f86edf8a810cad517a9534923
font_01_sfnt_off00015376.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15376 12252 bytes
SHA-256: 90fcf58ca865de211b610889848edef88847586f70a154b1fdecc6307866714f