Malicious PDF — malware analysis report

Static analysis result for SHA-256 a82cd6def16556a7…

MALICIOUS

PDF

74.2 KB Created: 2021-06-08 03:37:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: dfc6e3c327c8b3dab2f2e09072efac0b SHA-1: 505ce448631b386d25a7a1b7170613c18545411f SHA-256: a82cd6def16556a7365eecb7ab9d8ffb57978e22fe8198e5acdf24427a5b8dd6
126 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many pointing to disposable hosting services, indicating a link farm or SEO spam operation. The primary URL, 'https://infrive.ru/pbw?utm_term=all+formulas+of+maths+class+10+ssc+pdf', suggests a lure related to academic materials. While no scripts were explicitly extracted, the PDF structure and heuristic firings strongly suggest malicious intent, likely to drive traffic to malicious or spam websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 5

  • 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://infrive.ru/pbw?utm_term=all+formulas+of+maths+class+10+ssc+pdf PDF link annotation
    • https://vapovudinawixe.weebly.com/uploads/1/3/1/4/131437980/lonujer.pdfIn PDF document text
    • https://ruxabetuju.weebly.com/uploads/1/3/2/7/132740595/2815647.pdfIn PDF document text
    • https://vimanofadubob.weebly.com/uploads/1/3/5/3/135304206/jafujo.pdfIn PDF document text
    • https://woralolur.weebly.com/uploads/1/3/4/3/134359953/27b0fe2.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4478928/normal_602b84a75da00.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4446170/normal_602ef91023419.pdfIn PDF document text
    • https://reroweno.weebly.com/uploads/1/3/4/6/134687099/dijila.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4443608/normal_6047e285e0e19.pdfIn PDF document text
    • https://miruvogix.weebly.com/uploads/1/3/1/4/131408245/ripokifilosugozo.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4414688/normal_5fcddd8685670.pdfIn PDF document text
    • https://ruxakadun.weebly.com/uploads/1/3/0/7/130739963/e3e2a73b.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/be8c0ec9-d96b-4d73-a0f9-214e03a54afe/can_you_download_wii_sports_on_original_wii.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/eee44caf-9d47-45fc-8daf-04dea264077f/ladatunuvojitilomovi.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f8ecdfb9-d5ac-4324-ae22-d7699f3c6b3d/katzung_pharmacology.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/bfa8e948-f21a-4f53-a433-1d6483dab02d/70045922153.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/cbab45a9-10fb-4d55-90fd-81e3f0a278fd/what_is_family_tree_diagram.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/feab4a50-18bb-4d38-8e84-7facd07c548d/what_questions_are_in_the_5_minute_journal.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e4196365-20d8-465d-8da3-101f49a1f191/silabus_akuntansi_keuangan_lembaga_kelas_xii_kurikulum_2013.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1096a8d6-44e5-43db-adb2-4823f737ea2d/82022294766.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/77fb003a-b6f4-4ade-b7c0-b3dec4b90d55/cuanto_es_100_gr_a_oz.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d49d273f-fc7f-4403-bf4d-6d3e290edf1b/luzisid.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/bd82acf3-7793-4abb-9a43-1533d7e53ee2/ccna_routing_and_switching_complete_study_guide_2nd_edition.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/246160d2-65fb-44b6-8c52-53bcb034681b/20412810276.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_off0000e178.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE178 5580 bytes
SHA-256: 13262e90e0e7023c2350f6097199b8242d029223b3ec01b3817b85ea27250a32
font_01_sfnt_off0000f445.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF445 11316 bytes
SHA-256: b2de33a128d75a8f5573c6f6c2a8a8385749b994978688cfb2301f156f949e9d