Malicious PDF — malware analysis report

Static analysis result for SHA-256 3a3b0e604dedf6bf…

MALICIOUS

PDF

73.1 KB Created: 2021-06-13 08:54:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 993976efe5963e0f7e0b576a5975187b SHA-1: d6eba0477dd88801096a73e9cb90bfff38988823 SHA-256: 3a3b0e604dedf6bf4d697fff6227632d385fa70a46c71e35384d022d0baedcd7
126 Risk Score
Tags
free-cdn-ebook-manual-lure

Malware Insights

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

The PDF contains multiple external URIs, with one specifically pointing to a URL designed to compress PDF file size, acting as a lure. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a non-clustered link farm on disposable hosting, suggesting a phishing or malicious redirection scheme. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to download a second-stage payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 5

  • 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 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://krisoc.ru/pbw?utm_term=compress+pdf+file+size+to+5mb PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4468540/normal_6029296edffe5.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4410702/normal_60030beb240cc.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4421468/normal_60678b9195f98.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4460460/normal_5fda6c33e8f32.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://nomebazeregi.pbworks.com/w/file/fetch/144761862/71388645085.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f316c20c-5867-44ab-9c10-fe5e7bd53460/tabefupar.pdfIn PDF document text
    • http://penezilo.pbworks.com/f/libros_de_mecanica_industrial_gratis.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/106fa12a-0869-417a-a723-b50e9998e1d9/samabuferudopoxa.pdfIn PDF document text
    • http://tisowowuduwe.pbworks.com/w/file/fetch/144651957/gilbert_and_barresi_developmental_biology_12th_edition.pdfIn PDF document text
    • http://kuzimotum.pbworks.com/f/christmas_song_lyrics_quiz_printable.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e846ca24-dc89-4f40-b1f4-5398aca10b29/broadchurch_season_3_episode_1_review.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/03c5777e-af8e-4bad-a097-4650f64d63ac/xokajejuxoremufiwafojul.pdfIn PDF document text
    • http://lowigamivux.pbworks.com/w/file/fetch/144670626/75387392458.pdfIn PDF document text
    • http://kinuwibe.pbworks.com/f/how_do_you_connect_2_jbl_speakers_together.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e697c15e-d7e5-4128-8946-d9dd12fbd923/operations_research_major_jobs.pdfIn PDF document text
    • http://misabovu.pbworks.com/w/file/fetch/144713385/74054198993.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b5a4e9e6-d7b4-40de-b1e6-026ab2bebe66/najedod.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a3b02810-69f5-4eed-95fe-fff0d3765d63/tunum.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/fc781756-8640-4a04-a57a-ed295e344d06/tufefadu.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e461663e-9080-4bb3-a696-2b6a50b79bba/how_to_make_watch_stop_beeping_every_hour.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_off0000e10b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE10B 5196 bytes
SHA-256: ba52361007cd23daa4db08ef09f1a464748940563dc1424ac059044698c6cc75
font_01_sfnt_off0000f2a1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2A1 10812 bytes
SHA-256: bf562abb5ba1f00c1e0cc0610dbb2229d4a65d9cc3d991fe337036115ad8a44f

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