Malicious PDF — malware analysis report

Static analysis result for SHA-256 4d26c9ffaa824b27…

MALICIOUS

PDF

70.9 KB Created: 2021-04-01 06:45:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-21
MD5: 996bc4574edcf4dff2cf7645121de4a9 SHA-1: 63aaf1dd69adea75972bb9b44351461da83a9e2d SHA-256: 4d26c9ffaa824b279c57519c43170cdffd7a99c7e84d4dbfddb3f7e640d1ce7e
186 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains a large number of external links, many pointing to disposable domains, suggesting it's part of a link farm designed to redirect users to potentially malicious sites. The embedded content, though heavily obfuscated, appears to be related to the lure text "Venn diagram math questions", which is likely a pretext to encourage clicks on the malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://baarspo.ru/strik?utm_term=venn+diagram+math+questions PDF link annotation
    • https://tatazopizen.weebly.com/uploads/1/3/1/1/131163492/c01e779a2153.pdfIn PDF document text
    • http://datiwufirul.medianewsonline.com/accurate_english_a_complete_course_in_pronunciation.pdfIn PDF document text
    • http://puzexijabin.mypressonline.com/febevavep.pdfIn PDF document text
    • http://bijepitujutix.sportsontheweb.net/74713924646.pdfIn PDF document text
    • https://bazojosazim.weebly.com/uploads/1/3/6/0/136086377/nifakejejezogu-javojamu.pdfIn PDF document text
    • http://dugarudewemudo.sportsontheweb.net/environmental_health_risk_assessment.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/d84d5850-9fab-487a-aee5-01276f4eff8f/visixikipatefagefevusud.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/97e6cea1-dadf-47e6-883e-9e1a8f4336be/12281645389.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/cfd26697-5223-4c7d-bfc2-5a35ed797198/97741989843.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d2585147-2841-492f-ba9c-b696019b28b2/ingersoll_rand_air_compressor_2475f13gh.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d2df7aba-c076-4ae5-aec5-59313e8def9c/fg_knot_strength.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d364943f-094e-4c6f-8699-1f8cbdb7642d/82874301560.pdfIn PDF document text
    • http://xolavozezimodan.onlinewebshop.net/aprender_acordeon_de_botones.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/438e6250-2153-4099-8458-ed228ce71740/how_do_i_reset_my_samsung_s8_back_to_factory_settings.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/aedd10c5-3fb2-4ffb-87ae-e91d14f47576/xefadubogediv.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5b4fa370-9188-4f69-9fd3-7d25d907b871/reloading_powder_for_308.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_off0000d631.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD631 5300 bytes
SHA-256: 30cabdb50152aeb2f5f66f4a23447964f82a5009ca4feb6f7457e0fe7c5e7c2f
font_01_sfnt_off0000e802.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE802 10816 bytes
SHA-256: bf141f25c315a4830adb87a79ae5a0f3ae9e07496bf58d4dac91bac049d842d3

Open this report in the interactive analyzer, or submit your own file for analysis.