Malicious PDF — malware analysis report

Static analysis result for SHA-256 0d7784688b4ac132…

MALICIOUS

PDF

79.2 KB Created: 2021-10-18 09:10:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 8c235b1a7c95e2f2923bcd5330d5603d SHA-1: 4f0a40832ac7286b4fd74f81d0dffe020dbe7fc8 SHA-256: 0d7784688b4ac132360ad3aa207228cd7e7706f8906745fa4a82318bbeac257f
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ClamAV and an ML classifier, with heuristics indicating it functions as a link farm on disposable hosting. The embedded URLs, such as 'https://infrive.ru/uplcv?utm_term=boss+and+me+episode+14+subtitle+indonesia', suggest a phishing or malware distribution attempt. Although no scripts were explicitly extracted, the PDF structure and numerous external links point towards a malicious intent to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

Heuristics 5

  • 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 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://infrive.ru/uplcv?utm_term=boss+and+me+episode+14+subtitle+indonesia PDF link annotation
    • http://belv.ru/userfiles/file/xazosawemukod.pdfIn PDF document text
    • http://niezapominajkowo.eu/userfiles/file/wusab.pdfIn PDF document text
    • http://fpempresa.cen.es/userfiles/files/5021490971.pdfIn PDF document text
    • https://orderpoet.com/ckfinder/userfiles/files/97213064810.pdfIn PDF document text
    • http://artemon.nl/userfiles/file/xuxol.pdfIn PDF document text
    • https://www.sterlingsez.com/ckfinder/userfiles/files/jazafuvolufebofujebizew.pdfIn PDF document text
    • https://encouragingmath.com/wp-content/plugins/super-forms/uploads/php/files/aaaf94d2740e97dacd915d5fe09851d8/zajajebisamolopufumo.pdfIn PDF document text
    • https://vwb.mrv-educationservices.com/content_file/files/72214204122.pdfIn PDF document text
    • http://bernardthevenet.fr/ckfinder/userfiles/files/39606157193.pdfIn PDF document text
    • http://asiavent.com/UserFiles/file///58321371141.pdfIn PDF document text
    • https://francois-daulte.com/ckfinder/userfiles/files/rikapotixezejuwot.pdfIn PDF document text
    • http://polyacer-ecp.com/userfiles/files/20211010_145214.pdfIn PDF document text
    • https://doosradashak.in/ci/userfiles/files/ladike.pdfIn PDF document text
    • http://steakclubhn.com/campannas/file/sivenufiv.pdfIn PDF document text
    • http://alt-1c.ru/userfiles/file/65919588639.pdfIn PDF document text
    • https://tomas-music.com/contents/files/bilova.pdfIn PDF document text
    • http://sunriverps.com/data/editor/file/miligepogi.pdfIn PDF document text
    • https://vieclamlaocai.vn/webroot/img/files/1519896302.pdfIn PDF document text
    • http://skybuildinfraprojects.com/uploads/84813721434.pdfIn PDF document text
    • http://bridgestone-ice-cruiser-7000.ru/ckfinder/userfiles/files/tafasapekexunejutox.pdfIn PDF document text
    • http://windowsplusllc.com/ckfinder/userfiles/files/26755780284.pdfIn PDF document text
    • http://briquettemachinery.com/d/files/88004937372.pdfIn PDF document text
    • https://okud-istra.hr/userfiles/file/30470223777.pdfIn PDF document text
    • http://ecogestval.es/userfiles/file/38332184049.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://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_off0000ce3e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE3E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e650.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE650 18692 bytes
SHA-256: ea5f8887faa33aeb5ec023445e28caceab51e1368f248d032a6cbead629acf7c
font_02_sfnt_off000115f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x115F6 10876 bytes
SHA-256: 2fe500d9f5bd04e7c9bd89d55118dc7deee9c350f988be03903b44b44d120178