Malicious PDF — malware analysis report

Static analysis result for SHA-256 91205cec922547e3…

MALICIOUS

PDF

75.1 KB Created: 2021-04-11 13:01:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-06-30
MD5: 283bbc510a50bd14d522077977d43988 SHA-1: b71204ec2b29137b2a5219b3553d959cb0ec002c SHA-256: 91205cec922547e36d7209ca53b71a854ebcceea0c8d07977035b152be029bc2
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 pointing to disposable domains, indicating a link farm or SEO spamming operation. The embedded URLs and the heuristic firings like PDF_SEO_LINK_FARM and PDF_SEO_DISPOSABLE_LINK_FARM suggest the primary purpose is to redirect users to malicious sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://vilenefex.ru/strik?utm_term=fundamentals+of+organic+chemistry+7th+edition+solutions+manual+pdf PDF link annotation
    • http://vvd.bar/281914063045mm4v.pdfIn PDF document text
    • http://ig-copyrightviolation.com/formato_matriz_de_riesgos_gtc_45_2012_excelrh8j2.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4483586/normal_60600ec8419b7.pdfIn PDF document text
    • https://vidiwubiref.weebly.com/uploads/1/3/0/8/130874646/fimekowaguvex_zires_dofabozef_fulunizaz.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4479435/normal_5ffea3db88358.pdfIn PDF document text
    • http://madewithsunshine.com/21807396416gmbtj.pdfIn PDF document text
    • http://digitalcalakk1.xyz/havana_nights_invitation_template_freeqhxvj.pdfIn PDF document text
    • http://cardioactiveitalia.site/zijaradotutonelecji1j.pdfIn PDF document text
    • http://chempion.coffee/78892743134nrb5q.pdfIn PDF document text
    • http://omerkatanalp.com/crafting_and_executing_strategy_22nd_edition_citationxl86u.pdfIn PDF document text
    • http://brumbum6.xyz/hydro_dipping_tumbler_with_acrylic_paintl97wh.pdfIn PDF document text
    • http://studyweb.site/16384656510qh3nx.pdfIn PDF document text
    • https://devudupaf.weebly.com/uploads/1/3/4/8/134880603/fd339162d0b5.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/c7e48025-7783-4f48-a452-a20ae03e1fa6/cognitive_psychology_project_ideas.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/62fd797f-55cb-4c83-8d0f-99c916bcf345/37142518032.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3e0b3446-f4d8-4648-b2c4-a43884f860ed/grimoire_for_the_green_witch_a_complete_book_of_shadows_free.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9ab0a85a-ab16-4c94-8811-d312d3b4b21f/how_much_does_international_priority_mail_cost.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6f4af871-9ffa-44f2-a65f-0bd10dd2a8d9/torezavevogojuvewenenux.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/af7f9bea-0477-406f-bc8c-91bb42dbaa72/the_hound_of_the_baskervilles_setting_description.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/376c62e5-af8b-4d68-a349-589f6eed3e11/fejajatenelupugomex.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6ed220ba-61a3-4e80-9f8a-422e971e5dd8/95262774241.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
    • 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_off0000d024.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD024 5704 bytes
SHA-256: dfe3d626e6b2950a62cdefec350ae7ec6ddc11dc64ecf8433ecd151ced3d153e
font_01_sfnt_off0000e37e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE37E 10924 bytes
SHA-256: bd6185b1f67939314e5f2907149f0c62808cba5b1c51e96823560ae219b55eec
font_02_sfnt_off00010900.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10900 16204 bytes
SHA-256: e93acd332f5893643511f4cefd38969ad5c744ad1b08842a788b6be7d277dd15