Malicious PDF — malware analysis report

Static analysis result for SHA-256 37b0f59e3754ea07…

MALICIOUS

PDF

78.0 KB Created: 2021-04-07 20:02:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-10
MD5: 5002ce53b13ac59e5e7161fdf6fa2bf4 SHA-1: 01923f1a8ba148fb17920ff035ec427bf27ea35c SHA-256: 37b0f59e3754ea078b8100230a29bd914c7a28b186f99dcb0b437c36ea18b999
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. The ML classifier strongly flagged this PDF as malicious. The presence of embedded URLs and the structure suggest an attempt to redirect users to malicious sites, potentially for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://nipisod.ru/123?utm_term=how+to+calculate+your+carbon+footprint+worksheet PDF link annotation
    • https://pewituzusab.weebly.com/uploads/1/3/0/8/130874049/visugex.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4391915/normal_603f8dba1f888.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4423443/normal_5fe06500e9b6b.pdfIn PDF document text
    • https://dugubutufafug.weebly.com/uploads/1/3/0/7/130775350/0e3e1ccdc0.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4443602/normal_6030dff3dcfb0.pdfIn PDF document text
    • https://cdn.sqhk.co/purovufizu/LgeYfBe/65098566094.pdfIn PDF document text
    • https://cdn.sqhk.co/vikafaselida/03hixjc/how_to_cook_turkey_bacon_crispy.pdfIn PDF document text
    • https://vonewujin.weebly.com/uploads/1/3/1/3/131380349/2540355.pdfIn PDF document text
    • https://depesusexufajev.weebly.com/uploads/1/3/5/3/135351117/78d553bb1d82.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4501998/normal_603548b5781b8.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4405186/normal_605fd70ea606a.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4481841/normal_5fc901dc8629f.pdfIn PDF document text
    • https://cdn.sqhk.co/livulopo/heYiaNI/earth_wind_and_fire_devotion_song.pdfIn PDF document text
    • https://wimofitadaxota.weebly.com/uploads/1/3/4/3/134362004/labadaxawizonor_waxedetol_motepoju.pdfIn PDF document text
    • https://cdn.sqhk.co/venitalobeni/jbic3of/rifakonigenimerugetaz.pdfIn PDF document text
    • https://cdn.sqhk.co/geroterunetu/igdochb/sireves.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4422909/normal_603106c207017.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://1a6c606f-1efd-495f-9370-57f425d809fd.filesusr.com/ugd/1be480_ba419089bf5c40189fc7312a50d357ba.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/mupukesunobaga/24595646708.pdfIn PDF document text
    • https://be9ca920-c372-4566-b00d-544f92814f3b.filesusr.com/ugd/f0c5a9_53aa8bef50ce447a97042ddcdcc575da.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/tubupejevomo/66008380898.pdfIn PDF document text
    • https://s3.amazonaws.com/gulapore/kinadapivejizituvugas.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_off0000f1ae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1AE 5464 bytes
SHA-256: 70307cbfb4ab072fab810b8ff1ae2fdd06bb8e2214260ca5c9c5b6737af2ac15
font_01_sfnt_off0001044f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1044F 11228 bytes
SHA-256: 1bd7e2228a96d92aa5ac14d82c5181605a40912268e48d3a0699e9cc87012b8f