Malicious PDF — malware analysis report

Static analysis result for SHA-256 583c55b87b35fbcf…

MALICIOUS

PDF

89.5 KB Created: 2021-05-30 22:16:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-13
MD5: 5ee2cc518ca6367e6158ca52bee60459 SHA-1: 552274de713005fa0f9ff86a259a4b5a60fe97f7 SHA-256: 583c55b87b35fbcf2dd538dc2b1ed846ff1ca2527dd2fbf673f7e7decad9e1b9
186 Risk Score

Malware Insights

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

The PDF file 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 embedded URL 'https://midufefew.ru/strik?utm_term=what+kind+of+virus+is+hiv+quizlet' likely serves as a redirector to malicious content or a phishing page.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://midufefew.ru/strik?utm_term=what+kind+of+virus+is+hiv+quizlet PDF link annotation
    • https://static.s123-cdn-static-d.com/uploads/4488339/normal_60afe9c5ec77d.pdfIn PDF document text
    • https://nibuxapevu.weebly.com/uploads/1/3/4/6/134601724/viposivakuvupufi.pdfIn PDF document text
    • https://dizakevusarebiz.weebly.com/uploads/1/3/4/5/134581037/9092744.pdfIn PDF document text
    • https://rikomurisixub.weebly.com/uploads/1/3/1/4/131454733/ef5e063.pdfIn PDF document text
    • https://gojanevalu.weebly.com/uploads/1/3/4/3/134353606/2197ac38abb.pdfIn PDF document text
    • https://tojumemi.weebly.com/uploads/1/3/1/3/131379390/rexumejixuwi.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4369150/normal_603baea0e3b2d.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4368249/normal_6050ec9030781.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4483837/normal_5feb5c59070d4.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4371514/normal_5feb7bc5014c7.pdfIn PDF document text
    • https://pifabevab.weebly.com/uploads/1/3/4/7/134721676/683c4f0a6d2e4.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4375352/normal_5fe82c7d7b916.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4478125/normal_5fd2d8d791398.pdfIn PDF document text
    • https://rukiwopuxe.weebly.com/uploads/1/3/4/3/134340105/a3680a166e3d093.pdfIn PDF document text
    • https://disepijov.weebly.com/uploads/1/3/1/4/131438002/4489143.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4495409/normal_5fe3a919a0155.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4372737/normal_60403ce64035a.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4479707/normal_6021486765e42.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4387815/normal_60604f464ee48.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4417312/normal_603396034bd8b.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://medlineplus.gov/hivaidsandinfections.htmlIn 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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010b87.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B87 5308 bytes
SHA-256: a07a770eb8e043a33d58b81c1bd3cd7c1653778d5cbad3dd75897f74e9e98f68
font_01_sfnt_off00011daa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DAA 10916 bytes
SHA-256: aa6601ad264221bbb94e2ea1bd2a6a78ba489ae27bde6f2c1e3bf96b812f7f9a
font_02_sfnt_off00014301.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14301 16136 bytes
SHA-256: 4a82d930af4ff3021f3d19cbd37464c8e664c90bef13661c9db69df894853898