Malicious PDF — malware analysis report

Static analysis result for SHA-256 28a91a2af50e2c70…

MALICIOUS

PDF

83.8 KB Created: 2021-04-06 13:06:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-25
MD5: db7fbc4ff6d7e6eada5ae496f0a23686 SHA-1: 54fab39cc3fda6bf054f781c5be2226c164a7e90 SHA-256: 28a91a2af50e2c70df9922754ec9e9cfc5e652b8744540d5f00cd877a84a8aff
186 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9967

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://nipisod.ru/award?keyword=equations+of+motion+kinematics+pdf PDF link annotation
    • http://wapividazofar.scienceontheweb.net/boy_scouts_of_america_v._dale_case_brief.pdfIn PDF document text
    • http://falifipes.iblogger.org/star_wars_clarinet_sheet_music.pdfIn PDF document text
    • http://tojipipawerar.22web.org/wodokasazawal.pdfIn PDF document text
    • http://wijetaz.mypressonline.com/who_wrote_the_quran_quora.pdfIn PDF document text
    • http://zofunubesosena.mypressonline.com/pdf_text_to_speech_software_free_download_full_version.pdfIn PDF document text
    • http://lanujozawodu.sportsontheweb.net/galivubolutowunezefavan.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://1527c8d3-3321-4e9f-872f-e2bebb57bac2.filesusr.com/ugd/bf2d42_83c7f57433b84b7ba0b8cb921b07f137.pdf?index=trueIn PDF document text
    • http://sakikuzugodo.rf.gd/vabilujevumivuxekewoluwo.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d6e8b438-cd02-4d19-94b7-2e23d5248564/kwikset_z_wave_reset.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8ce791ec-6ed0-4df5-b3bf-8c832959a397/41375655743.pdfIn PDF document text
    • http://paritoxo.rf.gd/nobonep.pdfIn PDF document text
    • https://9df6e0af-a028-4e88-91ba-61a1b37318d5.filesusr.com/ugd/7c1f05_d31b4af419d0442a90f8cad539e04e06.pdf?index=trueIn PDF document text
    • http://gotikomerutoj.rf.gd/mogiluxujevikad.pdfIn PDF document text
    • https://3315be42-5dab-4b6e-b44d-105cb490973e.filesusr.com/ugd/2e3488_7cf7644002094148877f6ef5b09b1357.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/9aa544d0-85d6-42aa-9ec9-8519a5efae0b/poledekonibojoxu.pdfIn PDF document text
    • http://libejejizu.epizy.com/building_foundation_plan.pdfIn PDF document text
    • https://ac402fee-74f4-49a6-b5a4-6a03c6a057de.filesusr.com/ugd/b0cd75_cd877c0244764c91bdc799e6e9c843dc.pdf?index=trueIn PDF document text
    • http://vutegug.epizy.com/vowurafij.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/de3a7929-4b0d-4dd1-b85b-4d3df378276f/my_passport_wireless_pro_setup.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f2443994-a3ee-409d-b19a-aa94ab900486/the_jedi_path_book_review.pdfIn PDF document text
    • https://88e92b2d-3ddf-41b2-a2ae-4af48bfba274.filesusr.com/ugd/b74686_fda2ee6fc0bf4b4eb607f59a202b1b02.pdf?index=trueIn PDF document text
    • https://35b1a599-9f45-4897-82ce-59a931fc5495.filesusr.com/ugd/daca0d_f6f098f7c1924dc78c00d7720f2d97e4.pdf?index=trueIn PDF document text
    • http://kipixuge.epizy.com/boss_movie_songs_pagalworld.pdfIn PDF document text
    • http://zukepeva.rf.gd/ejercicios_tipos_de_enlaces_quimicos.pdfIn PDF document text
    • https://1b6fe947-be7e-4494-9a94-f566f178d3d1.filesusr.com/ugd/89064d_799c1eecd9484f08901d75dd7da104db.pdf?index=trueIn PDF document text
    • https://d7d9470a-9784-4c28-ac68-b1ab0f70ddf3.filesusr.com/ugd/148484_2ab3d812f9014150983a7f59d0733966.pdf?index=trueIn PDF document text
    • https://cf2e1f24-e5f1-4289-9567-3affce9c164e.filesusr.com/ugd/a4ea6c_01daa9c40df44529b05e6cdffb99ee55.pdf?index=trueIn 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_off000106c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106C6 5320 bytes
SHA-256: ae8f7e0dd685556a65f1aedb6a3bf52fc299544a743d98dd2971c9ab68b85dae
font_01_sfnt_off000118de.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x118DE 11836 bytes
SHA-256: f992f2037d0c5d217448f29e02bdc5b235870bade5a547654fb5670ca65b7b9e