Malicious PDF — malware analysis report

Static analysis result for SHA-256 caa49841479afdc3…

MALICIOUS

PDF

80.5 KB Created: 2021-03-10 19:57:57 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-22
MD5: c539a21ed78464a271c4c87d0114a6f9 SHA-1: 585146eb13e8abc3b5a5af03f7836ae13c5384f7 SHA-256: caa49841479afdc3fcf68481ce06ec15e30d6a12976ed02d033d1999d0602e7f
186 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

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://nipisod.ru/award?keyword=ece+aptitude+questions+and+answers+pdf+download PDF link annotation
    • http://ziwusis.getenjoyment.net/ruger_mini_14_scout_scope_mount.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4406473/normal_603808930f7d6.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4368243/normal_5fe8ba5ca362d.pdfIn PDF document text
    • http://mizifasurogik.mywebcommunity.org/excalibur_remote_car_starter_manual.pdfIn PDF document text
    • http://vijevejumozugim.sportsontheweb.net/gate_2020_syllabus_ece.pdfIn PDF document text
    • https://gopaxabog.weebly.com/uploads/1/3/5/3/135309926/d6c1adf437316.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4502248/normal_60340485bce2c.pdfIn PDF document text
    • https://dafelubuvotaxid.weebly.com/uploads/1/3/4/7/134753950/totawobazenifowobibu.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4489247/normal_6015b9a9ec9fd.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4456996/normal_5ff61e2e9418f.pdfIn PDF document text
    • https://zunexoxefa.weebly.com/uploads/1/3/5/3/135340588/4150964.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4485445/normal_6040c1fba985b.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4380699/normal_5fec3abc5b9f3.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4381964/normal_5fd60fd073f7d.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4417123/normal_5feb5fabeae69.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/foneniz/shires_brushing_boots_size_guide.pdfIn PDF document text
    • https://s3.amazonaws.com/goneduzum/bareilly_ki_barfi_mp4.pdfIn PDF document text
    • https://c480cc3d-c044-45b7-a7fa-747782367dcd.filesusr.com/ugd/a26f59_b66f17a8c5fb42c78b674153b0a6d673.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/xukirizugukugi/harry_potter_wands_diy_chopsticks.pdfIn PDF document text
    • https://3d7304b5-8527-495f-b913-615d6f357a43.filesusr.com/ugd/ef7486_47cc3c6456d848a084bfdeaa515370cf.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/dozore/94490191037.pdfIn PDF document text
    • https://368051e9-4199-40ea-b9a2-dc6e6f83cb3b.filesusr.com/ugd/6260fe_c73a4f7f77a743d09aaa79d18f670335.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/mesixadelomomo/sepsis_icd_10_guidelines.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_off0000ff32.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF32 5324 bytes
SHA-256: 44d9c2445f1dfbf8f8d387af6331c21573963cd25257557127c798b9077cad54
font_01_sfnt_off00011170.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11170 10228 bytes
SHA-256: 5ab2c888c91f89a41bf0e789f97a7dd4c332ce2401476187ee052e6a22cc5e6e