Malicious PDF — malware analysis report

Static analysis result for SHA-256 88bf6e714f4be918…

MALICIOUS

PDF

76.8 KB Created: 2021-05-12 00:33:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-22
MD5: d816a6659451f42b112c9d9ae1926cb7 SHA-1: e832b780903315cab380594ba2d4ff523fed3f09 SHA-256: 88bf6e714f4be91823a9227fdbb13ea379bd21b37a8ea1e25f1b7f04df83b893
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains a large number of external links, identified as a link farm. The ML classifier strongly indicated maliciousness, and the presence of numerous links to disposable domains and potentially SEO-manipulated content suggests a malicious intent. The primary function appears to be directing users to external resources, which could be for SEO spam or to host further malicious payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://pelibifir.ru/strik?utm_term=project+management+101+course PDF link annotation
    • https://cdn.sqhk.co/sevijeruba/gcidLii/transfer_news_twitter_barcelona.pdfIn PDF document text
    • https://cdn.sqhk.co/zaviresodew/ivzHwkF/54833508281.pdfIn PDF document text
    • https://cdn.sqhk.co/lisesemafo/SQT8Ctn/63199850684.pdfIn PDF document text
    • https://kufesivewafe.weebly.com/uploads/1/3/1/3/131384244/buxofuloro.pdfIn PDF document text
    • https://golakabuzoved.weebly.com/uploads/1/3/4/8/134870140/xiruzov.pdfIn PDF document text
    • https://pikemane.weebly.com/uploads/1/3/4/7/134775920/5225044.pdfIn PDF document text
    • https://cdn.sqhk.co/giravopakiw/hfjaoie/serumokovunizi.pdfIn PDF document text
    • https://telozigigozato.weebly.com/uploads/1/3/4/3/134310186/tiziwuxifigulexu.pdfIn PDF document text
    • https://cdn.sqhk.co/birugafomafo/hgjawje/95366388551.pdfIn PDF document text
    • https://cdn.sqhk.co/zixemoliz/0ggg6hf/telecharger_johnny_bonasera_3_apk.pdfIn PDF document text
    • https://jujowaganul.weebly.com/uploads/1/3/0/8/130874338/lugipanivepiwom-norolikirufemom-newofapojabaxe-rawirufi.pdfIn PDF document text
    • https://cdn.sqhk.co/widiroje/ihhhbZd/woridajigoriletafumudade.pdfIn PDF document text
    • https://siketaxugulus.weebly.com/uploads/1/3/5/3/135309361/82992c.pdfIn PDF document text
    • https://cdn.sqhk.co/tezofugowura/hgcgjeJ/wefex.pdfIn PDF document text
    • https://wudowured.weebly.com/uploads/1/3/0/8/130873715/sutujunix-domemes.pdfIn PDF document text
    • https://cdn.sqhk.co/woluzadeviv/jZHIxJ1/among_us_free_pc_download_without_bluestacks.pdfIn PDF document text
    • https://torurukiruxo.weebly.com/uploads/1/3/4/5/134529807/xudanokakonugiwim.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/jotizifime/80657328317.pdfIn PDF document text
    • http://bukuzem.rf.gd/brc_mesh_full_form.pdfIn PDF document text
    • https://s3.amazonaws.com/pizexopenaxu/bad_boy_ringtone_remix.pdfIn PDF document text
    • https://s3.amazonaws.com/remuv/57869982193.pdfIn PDF document text
    • http://fibubaxuvuvixik.epizy.com/3867641626.pdfIn PDF document text
    • http://jefesati.rf.gd/ketifolavakabatujekuf.pdfIn PDF document text
    • http://pufalidupoge.epizy.com/50169031637.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_off0000ee23.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE23 5356 bytes
SHA-256: 913b910d3eeaa932231acf73e29f31b8c7b9bd0bc9359f4a43bec2782b2fac23
font_01_sfnt_off00010048.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10048 11040 bytes
SHA-256: f9f1dfdc8763fd2f0e34b2698182a22ac5d8f8afed00e61fb3c967eabbaac42a