Malicious PDF — malware analysis report

Static analysis result for SHA-256 f926659f9217cec5…

MALICIOUS

PDF

81.1 KB Created: 2021-04-05 15:09:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-25
MD5: 050cc4be9c39bdec591ed4b301cfa93e SHA-1: 66ca9ad370b15a6a62a778cfebf6da637586390d SHA-256: f926659f9217cec5af1a42bd83f403c3f88526988111505fbaa235a492529f68
126 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It contains numerous embedded URLs, with a primary one leading to a link farm on disposable hosting, disguised as free online English courses. The presence of external URIs and the link farm structure suggest an attempt to redirect users to malicious content, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9954

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://dugedepap.ru/strik?utm_term=cursos+de+ingles+gratis+online PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4416490/normal_5fd9114bd9950.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4390373/normal_5fe35b71cb7c2.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4474475/normal_6053e92a4b164.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4414342/normal_5fed773a2b15d.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4391954/normal_60134b083cd96.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4410443/normal_5fe799de2cbf7.pdfIn PDF document text
    • http://afracheat9.xyz/pesuloxomis6t8yl.pdfIn PDF document text
    • http://ketrovk.xyz/best_fingerpicking_guitarists_in_the_worldhh2wp.pdfIn PDF document text
    • http://subuxiwubemew.getenjoyment.net/call_of_cthulhu_basic_spells.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4406170/normal_5fea003298aa5.pdfIn PDF document text
    • http://icily.xyz/que_tipo_de_comunicacin_verbal_hay83plt.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4475720/normal_5fdcc4ca4d5ad.pdfIn PDF document text
    • http://tufinanegonaj.medianewsonline.com/vorupewolojine.pdfIn PDF document text
    • http://porn77.design/what_is_turpentine_mineral_spiritsmdj20.pdfIn PDF document text
    • http://zalavsky.ru/24342275099nq24d.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/timeziso/exponents_and_logs_worksheet.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c9d32e4f-a91e-4dd9-a8bc-c0d2d0ba2032/76340989534.pdfIn PDF document text
    • http://fetekovabu.onlinewebshop.net/asus_rt-n12_d1_router_specifications.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0db1a709-8d5b-406f-bc5c-f4b9bee4262d/rocking_horse_winner_analysis_sparknotes.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0b66e1df-83bc-494c-a0f8-da0301488bec/gaxugosufesepeba.pdfIn PDF document text
    • https://s3.amazonaws.com/megujobemegor/91062864468.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7b95aee8-ec38-4c3f-97da-44a794e92d68/16457481807.pdfIn PDF document text
    • https://s3.amazonaws.com/mokixetat/62006257427.pdfIn PDF document text
    • http://tevefetilojas.atwebpages.com/gimoluverodanofagavopujo.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/00f7e255-cd78-4322-9c48-f399bdfb8ed6/kujebadokuloz.pdfIn PDF document text
    • https://s3.amazonaws.com/jiwisi/zatafab.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_off0000e8ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8CA 4896 bytes
SHA-256: 82af9119ef7a273b63d80d74dbcd87052fae3ac04f7f74086f44e8d28af12e37
font_01_sfnt_off0000f979.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF979 11584 bytes
SHA-256: 4dd005c79be1f0dab7f5019f59d2691431784e7caeb8bc2b0aa5c81d98a037c8
font_02_sfnt_off00011f6b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F6B 16204 bytes
SHA-256: 532315dfdc59b350d447ad91845dd8cc72a836e684f536ab9a4305dc5b53fb8e