Malicious PDF — malware analysis report

Static analysis result for SHA-256 937c8c4d922d2d23…

MALICIOUS

PDF

78.8 KB Created: 2021-05-15 21:05:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-22
MD5: 88b6702b30b44d025cb9e8f20ab3f2e0 SHA-1: f0f81c032b8752ee2e50c121688d7f5a4a556b5b SHA-256: 937c8c4d922d2d2300796746899771ff909378c607fcaecda381e49547c0e0f7
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, suggesting a link farm designed to redirect users to malicious sites. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and numerous external links are indicative of a malicious document, potentially leveraging embedded JavaScript for redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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://resalured.ru/strik?utm_term=what+is+needle+maintenance+on+my+keurig PDF link annotation
    • https://visosoduvevup.weebly.com/uploads/1/3/4/2/134234588/3863421.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4468838/normal_6009ebee5ce3e.pdfIn PDF document text
    • https://jawejeletisib.weebly.com/uploads/1/3/4/8/134886371/firojugip_fefubij_lufuvube.pdfIn PDF document text
    • http://ch-redirect.icu/vojabataxabepakazele30c1f.pdfIn PDF document text
    • http://it50disconto.info/customer_relations_supervisor_job_descriptionpz598.pdfIn PDF document text
    • https://rojanudase.weebly.com/uploads/1/3/0/9/130969060/91a9250.pdfIn PDF document text
    • http://sfr-webmail.com/17786405280q9h55.pdfIn PDF document text
    • https://vebodejivab.weebly.com/uploads/1/3/2/3/132302978/8bd327fa0.pdfIn PDF document text
    • https://zizipidefogin.weebly.com/uploads/1/3/4/8/134852386/347c7f2.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4369793/normal_60617132179ea.pdfIn PDF document text
    • http://rewita.fun/72968938902700mj.pdfIn PDF document text
    • https://juwaxevepatasi.weebly.com/uploads/1/3/0/8/130874094/midusisiti.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4446377/normal_6008185d47fce.pdfIn PDF document text
    • https://jolofoni.weebly.com/uploads/1/3/4/0/134042869/493476c2e9.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4391013/normal_604e4d803b659.pdfIn PDF document text
    • https://cdn.sqhk.co/moturalogupe/jiOjijC/vazimimawubokuwilewim.pdfIn PDF document text
    • https://lotepipi.weebly.com/uploads/1/3/1/4/131454034/sunegerikeresaxiz.pdfIn PDF document text
    • https://repowuvosifopel.weebly.com/uploads/1/3/6/0/136050091/kikaxo.pdfIn PDF document text
    • https://cdn.sqhk.co/dozawulu/jhdFCja/26279713179.pdfIn PDF document text
    • https://jukosixosibi.weebly.com/uploads/1/3/1/8/131871462/1ed9e0ff.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/gedimuta/cozee_home_fleece_fitted_sheet.pdfIn PDF document text
    • https://s3.amazonaws.com/ligole/how_to_make_a_simple_emp_jammer.pdfIn PDF document text
    • https://s3.amazonaws.com/sefukirexuwekij/reperejavuwajo.pdfIn PDF document text
    • https://s3.amazonaws.com/bezegoluzose/92845436532.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_off0000f567.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF567 5532 bytes
SHA-256: 6722021f4caccf555bcf67b5fd577e05a1797f7ddbbc62743b3ff2f3585000ed
font_01_sfnt_off00010820.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10820 11024 bytes
SHA-256: 58cd2002b640b0eb50a87722015b9bc9581609946f6412f7afbd79d2c2e3a52b