Malicious PDF — malware analysis report

Static analysis result for SHA-256 c57bb2b1df96ece1…

MALICIOUS

PDF

77.3 KB Created: 2021-04-01 17:14:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: 93d2e23959b58351359e1fa01da0ac71 SHA-1: a9b99537871c1a8614ec56739ab866fc6f7306e9 SHA-256: c57bb2b1df96ece1083976074c7fa547bf02d582f2b384aa23afad70b12375b2
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many hosted on disposable domains, indicating a link farm or SEO spam operation. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and embedded URIs are indicative of malicious activity, potentially leveraging embedded JavaScript for redirection or exploitation.

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://nipisod.ru/123?utm_term=channel+13+news+instagram+report PDF link annotation
    • http://lesagotefawa.22web.org/balancing_equations_worksheet_bbc_bitesize.pdfIn PDF document text
    • https://cdn.sqhk.co/xaselavub/ia650hg/51676465519.pdfIn PDF document text
    • http://bokifov.iblogger.org/periodic_table_short_notes.pdfIn PDF document text
    • https://cdn.sqhk.co/wafexumu/qihshbx/the_town_boyz_song.pdfIn PDF document text
    • https://cdn.sqhk.co/gusiloxi/Egjiihd/noxemiboponeget.pdfIn PDF document text
    • https://cdn.sqhk.co/tatudawo/58jabic/streamlabs_obs_mac_system_requirements.pdfIn PDF document text
    • http://immortal-sho.club/how_to_know_if_anything_is_wrong_during_pregnancyp50pv.pdfIn PDF document text
    • https://cdn.sqhk.co/texojijoraso/XDoA1ig/95871066359.pdfIn PDF document text
    • https://cdn.sqhk.co/pedajobu/gejehiM/25373459131.pdfIn PDF document text
    • http://kprovk.xyz/xarubepazenojemixafogawud9eva.pdfIn PDF document text
    • https://cdn.sqhk.co/tefulobesa/iLTYjdl/30691487501.pdfIn PDF document text
    • https://cdn.sqhk.co/molivovuki/ghfC4ih/cover_photo_facebook_psd_template.pdfIn PDF document text
    • https://wimukesogizat.weebly.com/uploads/1/3/4/6/134639197/d5fe44fb3d062bf.pdfIn PDF document text
    • https://warevinigipa.weebly.com/uploads/1/3/4/8/134898994/girapejosabelu.pdfIn PDF document text
    • https://kosopewoxi.weebly.com/uploads/1/3/5/3/135318270/nulezoxokusadi.pdfIn PDF document text
    • https://cdn.sqhk.co/bodorosuzuta/X0Gjihi/23827860000.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://fiwarirekagugen.epizy.com/33119709597.pdfIn PDF document text
    • http://jujilopuvij.rf.gd/menizu.pdfIn PDF document text
    • http://zenomidesedi.rf.gd/autodesk_maya_lt_2019.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_off0000ee35.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE35 5448 bytes
SHA-256: 658503d3229c10ed597530c3ceb180766e286c3ac62158f9d34a2584a8bc084b
font_01_sfnt_off000100a5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100A5 11524 bytes
SHA-256: a53d773324c4a7d30b4afd9dd0313aaf8cc4f45b4a8c21ba0864198493fc5a89