Malicious PDF — malware analysis report

Static analysis result for SHA-256 6550c08ccca57e0a…

MALICIOUS

PDF

76.7 KB Created: 2021-03-25 15:33:26 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-22
MD5: 3ff2a9b515341f46b2d26e99ed994c77 SHA-1: 26ec70c6d8a1993c728a6e0cfabb9a817b9e36a2 SHA-256: 6550c08ccca57e0a7c6c46ae3160a31aac3f60f1ee08c54623a5da4af03e7509
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 pointing to disposable domains and hosted on services commonly used for link farms and phishing. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and heuristics suggest it's designed to redirect users to malicious sites.

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://leonvi.ru/strik?utm_term=how+to+write+an+equation+for+slope+intercept PDF link annotation
    • https://cdn.sqhk.co/fukafodifi/cjbuejt/chuzzle_2_cash_out.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4446401/normal_600bf321c18ec.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4460968/normal_6027d6c0221e0.pdfIn PDF document text
    • http://zegererevez.medianewsonline.com/jhumpa_lahiri_short_story_interpreter_of_maladies.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4496380/normal_601c5b7bcf387.pdfIn PDF document text
    • https://pofofeteb.weebly.com/uploads/1/3/2/6/132681268/webilome.pdfIn PDF document text
    • http://jogajep.medianewsonline.com/37514604669.pdfIn PDF document text
    • http://jukexufepezaj.22web.org/woxejuserobidujar.pdfIn PDF document text
    • https://cdn.sqhk.co/mafowixodi/8iiqifU/genokawupazuliforaxe.pdfIn PDF document text
    • https://cdn.sqhk.co/givujelised/aWhbdih/90658187268.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4384828/normal_5ff594427fe52.pdfIn PDF document text
    • https://bipokedofep.weebly.com/uploads/1/3/5/3/135322207/9592662.pdfIn PDF document text
    • https://wevenakexeg.weebly.com/uploads/1/3/1/4/131438808/nirureluwofow-xebewebupekopos-muparadolizu.pdfIn PDF document text
    • https://vifazadaza.weebly.com/uploads/1/3/4/8/134883600/dowoxadofelom-katupita-zubutoregono.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://13fad4bf-7224-44b3-802b-16842e97d241.filesusr.com/ugd/b14664_b893a5fceee941efa95869ceed55a71a.pdf?index=trueIn PDF document text
    • http://vobuluga.rf.gd/72551364447.pdfIn PDF document text
    • https://f2f8a3c9-3ea7-4a25-b7e2-3e2749f32899.filesusr.com/ugd/f0e51d_c051096885bc4f2c98160ade760745b8.pdf?index=trueIn PDF document text
    • https://32cf4326-ba62-484c-a3ca-05d02c2dd2e5.filesusr.com/ugd/0b46e6_7a9b6a64c5eb47e4b250e7ad9d93d1ee.pdf?index=trueIn PDF document text
    • https://f84ffea9-2755-49c2-9cb5-47ca8b55fe65.filesusr.com/ugd/0adedf_39e663b8999349f6998d0c666c5992b5.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_off0000df9a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF9A 5072 bytes
SHA-256: 8465dc400c6769fb6e5ace699714e288551b38cf5b9096ae5a7a2d71641c19da
font_01_sfnt_off0000f0fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0FC 11252 bytes
SHA-256: fdd45b63de66ed7a4d28545d6a0a649865a9461b38e85651c9d4b8afb66127de
font_02_sfnt_off0001178b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1178B 4324 bytes
SHA-256: 9f355172d696dda274cac500966718f112ce76951f19577ac4888987ea6471b2