Malicious PDF — malware analysis report

Static analysis result for SHA-256 3f0100c6ab83df43…

MALICIOUS

PDF

80.9 KB Created: 2021-03-20 09:48:34 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: 7158aeaf1defdb282d89acb619f4def8 SHA-1: 248c3f2e3511af51cc92026c369f5d6e83cfbb67 SHA-256: 3f0100c6ab83df43ce9a0e68417468906a41ec25f74f72539df7cad5601f066b
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, indicating a link farm or phishing attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. The document body, though heavily obfuscated, contains keywords related to 'Swann dvr fan replacement' and 'wkhtmltopdf', suggesting a lure to potentially malicious websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://baarspo.ru/strik?utm_term=swann+dvr+fan+replacement PDF link annotation
    • https://rixonusoraj.weebly.com/uploads/1/3/0/7/130738646/f84c1a3.pdfIn PDF document text
    • https://bigubuwona.weebly.com/uploads/1/3/4/3/134309174/sijonuvozusunuw.pdfIn PDF document text
    • https://gerunujixode.weebly.com/uploads/1/3/1/6/131606408/1900040.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4465024/normal_5ff93433ccd42.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4496824/normal_60167597d3224.pdfIn PDF document text
    • https://bagubabijotete.weebly.com/uploads/1/3/4/3/134319258/481919.pdfIn PDF document text
    • https://rajuputodetu.weebly.com/uploads/1/3/4/6/134682309/bd70e3d4765e.pdfIn PDF document text
    • https://didunoduwogu.weebly.com/uploads/1/3/2/6/132682107/d5ac8989.pdfIn PDF document text
    • https://zugudomumomaxix.weebly.com/uploads/1/3/5/3/135324912/veluzeriko-sesipepo-nuvixon-rojisunip.pdfIn PDF document text
    • https://lajexupizad.weebly.com/uploads/1/3/0/7/130775806/suzar.pdfIn PDF document text
    • https://tofariviviri.weebly.com/uploads/1/3/4/1/134109347/nelitu.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://f2d828cf-06d9-46ea-85af-d88b0bc20d44.filesusr.com/ugd/501a20_855a8b5217334c509aca65e842e09fa9.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/zagapaxa/teaching_phonics_worksheets.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ebf113e6-a4ed-4029-8944-42b4395f557d/11379906511.pdfIn PDF document text
    • https://s3.amazonaws.com/bidurudilidujug/bigo_live_tv_app.pdfIn PDF document text
    • https://s3.amazonaws.com/novipaliwid/kisunebumoturomupufop.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a0e53e8a-685f-453b-a891-5cbb6dce139c/19293557884.pdfIn PDF document text
    • https://9d1e48ad-bcd7-4831-9b7b-7108443a63b6.filesusr.com/ugd/136d07_56b545fa2c7643bda3d551bc95ed7d33.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/kavifunaruvi/abstract_algebra_with_applications_terras.pdfIn PDF document text
    • https://da99f664-88c7-4a27-98aa-0bbcec2e8f57.filesusr.com/ugd/66f3f9_5617db648259436d87289d0e0fb3de4c.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/f5525c32-9e15-4e2b-aa59-7c16569358c2/how_to_potty_train_baby_in_3_days.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_off0000f2d2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2D2 5008 bytes
SHA-256: f58860eaa408498597bf38e3be457e93f981db30c120e5c5fd5b1a4d06396948
font_01_sfnt_off000103cd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103CD 10728 bytes
SHA-256: 9d2e9eaabc288f723de10258c2211359586eb94ad3922da037e2766d38c0cc95
font_02_sfnt_off00012897.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12897 4324 bytes
SHA-256: d1f4a20f0e35a0564be54678b929bb8c711862c507f070c2b9a6abea8daf4378