Malicious PDF — malware analysis report

Static analysis result for SHA-256 57f3b5daff25f1db…

MALICIOUS

PDF

99.2 KB Created: 2021-03-21 07:57:31 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-06-20
MD5: 039aef3c449eef93a8b7b61c49ffb9e2 SHA-1: 572bd6ebfe2fb6c29eb8378d6497a32a773bc0a1 SHA-256: 57f3b5daff25f1db468c2f378f089b5f32305f64d5f03c9badd49ca724f3986e
184 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics as malicious, including a critical alert for linking to known malicious redirector infrastructure. The embedded links, such as 'https://dafemum.ru/award?keyword=punctuation+rules+pdf+oxford', are designed to lead users to potentially harmful sites. The document body, though heavily obfuscated, contains metadata suggesting it was generated by wkhtmltopdf, a tool often used to create malicious PDFs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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
  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • 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://dafemum.ru/award?keyword=punctuation+rules+pdf+oxford In PDF document text
    • http://malolufixanovas.sportsontheweb.net/cambridge_primary_checkpoint_past_papers_2020_maths.pdfIn PDF document text
    • https://jodajapiguzok.weebly.com/uploads/1/3/2/7/132710756/1923053.pdfIn PDF document text
    • https://pulezigo.weebly.com/uploads/1/3/4/6/134600697/ac5d9cb.pdfIn PDF document text
    • https://dubilovatigalis.weebly.com/uploads/1/3/4/7/134701517/xilawipesisoj_defogugitam.pdfIn PDF document text
    • http://vitofemegawe.getenjoyment.net/tijanesutul.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4528915/normal_6035d6ef48780.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4449599/normal_6031b73ee1cd2.pdfIn PDF document text
    • http://lanizimugigil.getenjoyment.net/67030109747.pdfIn PDF document text
    • https://kopomitesukov.weebly.com/uploads/1/3/1/4/131453216/rawoxu_vetupekaj_juloziveja.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4413004/normal_5fc97808ca841.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4477137/normal_5fe72285bce14.pdfIn PDF document text
    • https://betepojikimiji.weebly.com/uploads/1/3/0/8/130874485/jidide_diwetotoruwi_nazitusibapu.pdfIn PDF document text
    • http://lolebunefa.iblogger.org/application_for_leave_format.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4427097/normal_5fd60c95ecba1.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4427544/normal_5ffcd1b932b2c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4454168/normal_6044d07e55fdb.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4455376/normal_5fdc8b1474cce.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4366366/normal_6000237490a8c.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://suwuriru.onlinewebshop.net/basuresafowum.pdfIn PDF document text
    • http://kisolapuri.rf.gd/online_spoken_english_tutor_jobs.pdfIn PDF document text
    • https://s3.amazonaws.com/masevewi/topusizigatukar.pdfIn PDF document text
    • https://s3.amazonaws.com/sixolose/clinical_mental_health_counselor_salary_by_state.pdfIn PDF document text
    • https://s3.amazonaws.com/livivuvuwugeb/oxford_ib_chemistry_textbook_answers.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

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000145d3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x145D3 5216 bytes
SHA-256: b199a96f34a74404549960423382e2d83427ed3a29bc76567acb2f1a69aef32b
font_01_sfnt_off000157a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x157A7 11608 bytes
SHA-256: e85299a74412351ebd2052dfe5531530038886a966980e3d0da423c091e1e0bb