Malicious PDF — malware analysis report

Static analysis result for SHA-256 b8cf1ea8dd9abcdd…

MALICIOUS

PDF

74.8 KB Created: 2021-05-27 03:11:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 80e87bba06a138b2a2ab5f2c921f81cf SHA-1: 8b4c57bbd3f3191cbc3155b03ae72f2d048c7959 SHA-256: b8cf1ea8dd9abcddb1474328a51ca53a28ad9c6da4e730b8d699acd45f613710
186 Risk Score

Malware Insights

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

The PDF file contains numerous external links, many pointing to disposable hosting services, suggesting a link farm or phishing operation. The embedded URL `https://midufefew.ru/strik?utm_term=game+hacker+apk+3.1+no+root+latest+version+download` indicates a lure for downloading potentially malicious software. ClamAV and ML classifiers also flagged this PDF as malicious, specifically as a phishing trojan.

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
  • 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/strik?utm_term=game+hacker+apk+3.1+no+root+latest+version+download PDF link annotation
    • https://kadogejajufa.weebly.com/uploads/1/3/4/7/134717900/c5292483045.pdfIn PDF document text
    • https://bopazexujow.weebly.com/uploads/1/3/4/8/134876268/wafegu.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4391909/normal_601d99d9c5cc0.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4405420/normal_5ffbcb558ed6f.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4459939/normal_602f72d5e19ea.pdfIn PDF document text
    • https://lotetirupaxep.weebly.com/uploads/1/3/4/0/134013035/lizovevavad_pifepomidonof_netid.pdfIn PDF document text
    • https://kewikadovus.weebly.com/uploads/1/3/4/7/134746666/wemokugax.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4450517/normal_5fdb1cb6631a6.pdfIn PDF document text
    • https://tijanowu.weebly.com/uploads/1/3/0/7/130739502/2841201.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4420752/normal_602058e11fd51.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4470211/normal_604818c9ee460.pdfIn PDF document text
    • https://bezodidamivozel.weebly.com/uploads/1/3/2/6/132683328/361462.pdfIn PDF document text
    • https://fapizorimuko.weebly.com/uploads/1/3/1/1/131164308/13648.pdfIn PDF document text
    • https://mexugagerow.weebly.com/uploads/1/3/4/4/134482965/mimigu_dinezafegatito_zekivagibuj.pdfIn PDF document text
    • https://depoferi.weebly.com/uploads/1/3/4/4/134445349/8214696.pdfIn PDF document text
    • https://nurojitare.weebly.com/uploads/1/3/2/6/132682966/nojupunedib.pdfIn PDF document text
    • https://zesozekoxetaba.weebly.com/uploads/1/3/4/4/134497604/wafof.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/60ee0d5e-a038-4978-aafd-d3beb4451c7e/kowemulonubuginavepifibu.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f0eea39d-d7be-444d-a778-9a77de167c40/korg_sq_10_usato.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f4adf828-6ec5-4e20-b8e6-a1fdb9e4c227/mefajetuxagivunadud.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/65c5768f-7ebd-4d2f-a4c7-86554b756df4/dagebaxi.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_off0000e5f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5F7 5808 bytes
SHA-256: c5db9a91f2166e452bcea76eb7342345207ed6e84c7bfd62a3b1311e349a29fb
font_01_sfnt_off0000f9b5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9B5 10644 bytes
SHA-256: da9ecb91ad96727a9857e6cf0da75ca7b1a6ae5f03fbfae96d0f41290ff22c52