Malicious PDF — malware analysis report

Static analysis result for SHA-256 0b34ef8618efb39f…

MALICIOUS

PDF

73.3 KB Created: 2021-03-18 04:21:11 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-02
MD5: 1b135f98d23d32153233345dd48a54ca SHA-1: 796613a0062418c814467cd16a82ede6802b09bd SHA-256: 0b34ef8618efb39f1376e5f8cc23784dd88659c05d0fbc962177259414130d69
226 Risk Score

Malware Insights

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

This PDF document contains a large number of external links, many pointing to disposable hosting, suggesting a link farm or SEO spam campaign. The presence of an invisible link to 'securityofusersdevicesonline.site' indicates a phishing or malicious redirection attempt. The ML classifier and ClamAV detection strongly support its malicious nature, likely as a phishing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 7

  • 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.
  • Image-heavy PDF with invisible link to suspicious domain high PDF_SUSPICIOUS_LINK_LURE
    PDF is a small image-heavy lure with invisible link annotations that send the user to a suspicious high-risk-domain URI. This matches credential-phishing carriers where the visible document is only a prompt and the real collection flow happens on the linked website.
  • 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://botokaw.ru/strik?utm_term=composition+of+trig+functions+and+their+inverses PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4408599/normal_6028357768226.pdfIn PDF document text
    • https://cdn.sqhk.co/dewufidabo/sHJHhjb/55846848490.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4420025/normal_5fea01ae3798f.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4408483/normal_6029990c48e13.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4401983/normal_5fd90d0dccef8.pdfIn PDF document text
    • http://securityofusersdevicesonline.site/aqa_gcse_biology_book_answersygzyt.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4372681/normal_6018efa149dc9.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4448103/normal_602aae5988794.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4369190/normal_60041c082e42b.pdfIn PDF document text
    • https://cdn.sqhk.co/vimewiki/heQqhhi/card_crushers_multiplayer_monster_battle_tcg.pdfIn PDF document text
    • https://waforavorodi.weebly.com/uploads/1/3/4/3/134314120/liwiren.pdfIn PDF document text
    • https://xiluxobafuju.weebly.com/uploads/1/3/5/3/135323992/saragoxepesufosuk.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4379035/normal_5fda6b5c13c81.pdfIn PDF document text
    • http://trastqort.online/xotodabofaba0o6o.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4371523/normal_60364a89437fa.pdfIn PDF document text
    • http://fherixq.com/love_to_draw_manga_gacha_life52fta.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://8a833fea-7c9a-4d2e-a5a7-d3590f42a3e5.filesusr.com/ugd/9aab09_5ba6de080c0445a88229c5dc795cb161.pdf?index=trueIn PDF document text
    • https://7aff118d-26f6-4d76-9bc9-1838009e7274.filesusr.com/ugd/f80014_67d9e2f0250742c28327d8e53f3c18a9.pdf?index=trueIn PDF document text
    • https://ec2d952e-5494-46d8-b841-fee222248b17.filesusr.com/ugd/9713d5_37309868d5234041a30e4bc6c69704f9.pdf?index=trueIn PDF document text
    • https://af0fe010-594a-4ec7-a26b-e2d78e33490d.filesusr.com/ugd/7d2910_07f41d3e8df14124bed4a1dc3530506a.pdf?index=trueIn PDF document text
    • https://ee60c613-3dd1-430d-b711-08e3dcbf0273.filesusr.com/ugd/19ce5d_9c1cce232c40405f8d2f7bfe97ed78ff.pdf?index=trueIn 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_off0000dfeb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFEB 5504 bytes
SHA-256: 0f11d46cecf88ee959efe110fd192951a7c372ff0c0c407260fad25796449f8f
font_01_sfnt_off0000f27b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF27B 10956 bytes
SHA-256: 14015f4e31ddaefd9fad7b47034d4995afafe858b21813e235833a4aa950c357