Malicious PDF — malware analysis report

Static analysis result for SHA-256 1041c08b672352dc…

MALICIOUS

PDF

80.7 KB Created: 2021-03-11 19:41:48 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: 1c318787f0e2b0ab277c8ca93949a6d3 SHA-1: e8b22502f34430a6c5bd5b2c4af82227a2f34f60 SHA-256: 1041c08b672352dc9c37fab31ec44b114302e61ba3467f19109db1fe61f15f37
186 Risk Score

Malware Insights

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

This PDF file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The document contains a large number of external links, many pointing to disposable domains, suggesting a link farm or SEO spam operation. The presence of URLs like 'https://kuzutuzo.ru/123?utm_term=chemistry+practical+file+class+12+pdf' indicates an attempt to lure users with deceptive content. No scripts were extracted, but the overall structure and heuristics point towards a phishing or spamming attack vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://kuzutuzo.ru/123?utm_term=chemistry+practical+file+class+12+pdf PDF link annotation
    • https://cdn.sqhk.co/vumojakizaw/dOgjpXh/rock_climbing_classes_for_adults_near_me.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4411218/normal_600317370c58a.pdfIn PDF document text
    • http://pitikudefojeken.getenjoyment.net/what_are_the_symptoms_of_a_bad_pcm.pdfIn PDF document text
    • http://ponaxamewimenul.sportsontheweb.net/85365658157.pdfIn PDF document text
    • https://mugakosi.weebly.com/uploads/1/3/1/3/131379948/4186063.pdfIn PDF document text
    • https://bekalerobo.weebly.com/uploads/1/3/5/3/135346313/8126817.pdfIn PDF document text
    • http://warajuvevuv.medianewsonline.com/35492221716.pdfIn PDF document text
    • https://cdn.sqhk.co/jiguluzufuwa/jruB8hf/85092903924.pdfIn PDF document text
    • http://zixivudu.getenjoyment.net/10th_class_maths_formulas.pdfIn PDF document text
    • https://cdn.sqhk.co/vivepovugeli/jUsfNgg/gavamumovugibo.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4490128/normal_5ff71c5d2098f.pdfIn PDF document text
    • http://gisoboxizaza.mygamesonline.org/100_chart_with_missing_numbers.pdfIn PDF document text
    • https://cdn.sqhk.co/vozevadijut/Ljbiclv/58060239469.pdfIn PDF document text
    • https://cdn.sqhk.co/baxotonad/iir7LAo/352565884.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://6d5fec37-5936-4ae8-8938-03a86e982f09.filesusr.com/ugd/d4da64_bb5139b3aa434404a522086dca8b7d87.pdf?index=trueIn PDF document text
    • https://60f6da8c-824c-4163-aae9-6195f2ac7ed4.filesusr.com/ugd/7f16bd_bc985e46c23f40feb2c8a6d28d3a00be.pdf?index=trueIn PDF document text
    • https://c4a5d104-04f9-44e6-b03f-1f5edac3680f.filesusr.com/ugd/f23921_9c3a14cf2fc34fa79695f2583a4176bc.pdf?index=trueIn PDF document text
    • https://bf130ee1-1463-4c69-9604-1b23772ced92.filesusr.com/ugd/b4609a_872e1b3e56a34611a5fe9284a40e6a66.pdf?index=trueIn PDF document text
    • https://c3a7a64c-5591-430b-94d7-c2eadfdf3523.filesusr.com/ugd/966478_f862f921d8774ee9926aeebfddc2545e.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f2e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2E4 5588 bytes
SHA-256: 489dd80b1241bf052e94512249b97a728498349d3c2ed838fe7107210199d3a9
font_01_sfnt_off000105b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105B6 2116 bytes
SHA-256: 991f7ef292b59849fa1804c361c52a6255426db797fbcab3b5d31d1f34ee76c9
font_02_sfnt_off00010f61.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F61 11000 bytes
SHA-256: c38f5672142e36109eb1c0d3c3b31d416bc14aeec112d26f3be8126a1ad7e4fc