Malicious PDF — malware analysis report

Static analysis result for SHA-256 b1a87a6729166061…

MALICIOUS

PDF

68.3 KB Created: 2021-02-28 21:57:07 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-07
MD5: f44ef3dd20a32321e0613270310ccedf SHA-1: 7fb2a7bd7c810217d601495f587624aa36f1e8bf SHA-256: b1a87a6729166061fa85a23dcd7c08a398d01de2b740a24d86f576c8b3be15dc
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, suggesting a link farm or SEO poisoning tactic. The primary URL, 'https://xezojetit.ru/award?keyword=2005+nissan+frontier+transmission+valve+body+for+sale', is presented as a search result for car parts, likely to entice clicks. ClamAV and ML classifiers strongly indicate malicious intent, specifically phishing. No scripts were extracted, but the PDF structure itself facilitates the redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://xezojetit.ru/award?keyword=2005+nissan+frontier+transmission+valve+body+for+sale PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4408596/normal_60231a40e1c4e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4367667/normal_5fd8e37760686.pdfIn PDF document text
    • https://limorevoxa.weebly.com/uploads/1/3/4/6/134611026/tidar.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4413120/normal_5fd3bfaec1103.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4459058/normal_5fdbdb2378d63.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4470835/normal_60367ccf91179.pdfIn PDF document text
    • http://jofufuzutaki.22web.org/83328460336.pdfIn PDF document text
    • https://fiwobezamarevev.weebly.com/uploads/1/3/2/7/132740324/6721303.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4385424/normal_603033c06ef31.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4413707/normal_6020866059d94.pdfIn PDF document text
    • https://zajebujop.weebly.com/uploads/1/3/4/9/134902249/tajopefimol_gojogerejo_xebuwi_petidujojomepe.pdfIn PDF document text
    • https://gakulenem.weebly.com/uploads/1/3/1/4/131437742/vuposebika.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4459630/normal_603217ae98ad6.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/wudibirewuduto/26129146612.pdfIn PDF document text
    • http://tomunipi.rf.gd/sipeed_k210_datasheet.pdfIn PDF document text
    • http://muduwabu.rf.gd/weather_and_climate_worksheet_answers.pdfIn PDF document text
    • https://s3.amazonaws.com/firudegix/android_17_quotes_dbz.pdfIn PDF document text
    • https://s3.amazonaws.com/fupanabivote/committee_on_climate_change_progress_report_2018.pdfIn PDF document text
    • https://s3.amazonaws.com/liluvad/governed_portfolio_6_fund_factsheet.pdfIn PDF document text
    • https://s3.amazonaws.com/nuselufuzo/rezamugesom.pdfIn PDF document text
    • https://s3.amazonaws.com/pasutiz/liberty_shoes_ltd_annual_report_2018.pdfIn PDF document text
    • http://wuboxobotuz.rf.gd/durawegupunajet.pdfIn PDF document text
    • https://s3.amazonaws.com/rujabepifar/tapibunaxuvofesinixi.pdfIn PDF document text
    • https://s3.amazonaws.com/zufojadibi/accp_chest_vte_guidelines.pdfIn PDF document text
    • https://s3.amazonaws.com/nuxulikiwab/school_calendar_template_2019.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_off0000cde2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCDE2 5660 bytes
SHA-256: d6993773673b333bb9a30432086716b4e90388d1d7f293c892c82059e3cb4904
font_01_sfnt_off0000e112.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE112 9996 bytes
SHA-256: c5e7e350ccbaccbde8c30fe6ff123b2e0d2928ee2c79da9368add66c862ba0a0