Malicious PDF — malware analysis report

Static analysis result for SHA-256 81ad58b4aeeab184…

MALICIOUS

PDF

84.9 KB Created: 2021-03-24 03:10:54 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: 63e9adfb00635f82bf74fed3faac24b8 SHA-1: e5c851c85deb8b1e8abe920961b7acd20022c2a1 SHA-256: 81ad58b4aeeab184a681beb379e2b297b6b61ce913c9271528ae4ac58275532d
126 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs, with a high heuristic indicating it functions as a link farm hosted on disposable domains. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for distributing malware or phishing content. While no scripts were directly extracted, the PDF structure and embedded links are indicative of a malicious document designed to redirect users to harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

Heuristics 5

  • 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 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://gimoguvi.ru/wix?keyword=synaptic+signaling+is+more+common+in PDF link annotation
    • http://help-igcopyright.xyz/55903593880k0u1m.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4471230/normal_601133dc31204.pdfIn PDF document text
    • http://nenodipemuxok.mypressonline.com/64438309469.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4450516/normal_60506392d46d2.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4380539/normal_602f8a9bd6cff.pdfIn PDF document text
    • http://kovamuwaropepu.getenjoyment.net/bsc_nursing_4th_year_syllabus_download.pdfIn PDF document text
    • http://sinoxaju.mygamesonline.org/is_the_crown_season_2_true.pdfIn PDF document text
    • http://bossyonlinex.com/brazil_visa_application_form85r8b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4368972/normal_6039f88047ed4.pdfIn PDF document text
    • http://hr-insider.com/peliculas_de_barbies_en_espaol_comp9876c.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/wanasuvedigo/79131879463.pdfIn PDF document text
    • https://769966b8-4adc-437e-bba8-f198cf6e171b.filesusr.com/ugd/41a0b6_3328044d46f94880b70fdfd8d0a5e49b.pdf?index=trueIn PDF document text
    • https://02408c19-b9f6-4996-a596-1d5b7e46c8d3.filesusr.com/ugd/c83fdb_1598da9d741f4cfcaecfb5646ba4fa1e.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/kumasala/how_to_repair_a_rug_doctor.pdfIn PDF document text
    • https://79d86aa2-23c4-4aa0-a0dc-c16ac59ae55d.filesusr.com/ugd/ecb701_b9adc967a2814ee5b73c13d61bf8018c.pdf?index=trueIn PDF document text
    • https://f84ffea9-2755-49c2-9cb5-47ca8b55fe65.filesusr.com/ugd/0adedf_05bc3fa9c7954b699fe6f1b9bc96c317.pdf?index=trueIn PDF document text
    • https://07d68bf2-0661-47e2-9ffe-eae068a071af.filesusr.com/ugd/fef806_ee43346d12fa49c195f5f8d601e3d7fb.pdf?index=trueIn PDF document text
    • https://f1e11ea9-a931-46ad-af30-391325c877dd.filesusr.com/ugd/423518_3329e27078f94e97ae12d8ae0341a3ba.pdf?index=trueIn PDF document text
    • http://laxukumelukadut.myartsonline.com/bipijowekiweloru.pdfIn PDF document text
    • https://ef2e072a-e8a2-4438-804d-cc750be2e2f6.filesusr.com/ugd/6a22cb_8ed269f3cdb94550a343caf99c257121.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/rupatojuko/baby_clothes_bunting_template.pdfIn PDF document text
    • https://s3.amazonaws.com/fixararololu/stoichiometry_mole_to_mass_problems_answer_key.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_off0000f57b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF57B 5456 bytes
SHA-256: 5a074c0d22f1633338ed959bde00c38b4871c799a0d194c12bc6b0b2daf7e74f
font_01_sfnt_off000107fe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107FE 12256 bytes
SHA-256: 6245f91ee7e7c4523b57689346c532d7bd5f06063697db1e2a818920ee94afb1
font_02_sfnt_off0001310d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1310D 16036 bytes
SHA-256: 354dce64f07f3d7acdf6a04edf763950ffbfec4edcbb4bfe17b65a83544077bb