Malicious PDF — malware analysis report

Static analysis result for SHA-256 8b9c27ca3034e468…

MALICIOUS

PDF

78.7 KB Created: 2021-03-06 21:42:01 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-29
MD5: 8f2ce2510a99e54fb3f1cc86320df4b3 SHA-1: 2d77e51b392d3576a9d12e3e6bae433f88aec29c SHA-256: 8b9c27ca3034e468e67f8afd38ede785ec573f84ee55d64b198787409541f04f
166 Risk Score

Malware Insights

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

The PDF contains multiple heuristics indicating it is a link farm and uses suspicious, invisible links to external domains. The ML classifier and ClamAV detection strongly suggest malicious intent, specifically phishing or malware delivery. While no scripts were explicitly extracted, the PDF structure and embedded URLs point towards an attempt to redirect users to malicious sites.

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
  • 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://bologen.ru/strik?utm_term=how+to+get+big+legs+with+bodyweight+exercises PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4369503/normal_5ff7c15eef275.pdfIn PDF document text
    • https://cdn.sqhk.co/zixemoliz/2Dzgcgj/funny_whatsapp_status_in_bengali_download.pdfIn PDF document text
    • http://kkkirrreeee.space/lugubanajowetelzsyz6.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4461766/normal_5ff1f87012539.pdfIn PDF document text
    • http://natur-bio.space/security_analysis_grahamucvny.pdfIn PDF document text
    • https://cdn.sqhk.co/mofipife/hcQr9PT/42396727561.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4449424/normal_5ffd7e39c0ea4.pdfIn PDF document text
    • http://procripton.com/zuxibanolusuzaxafobes42kqw.pdfIn PDF document text
    • http://com-signto6.xyz/tagaxanexaguwodedasjbv5k.pdfIn PDF document text
    • https://cdn.sqhk.co/tokofape/heidfgh/89871637457.pdfIn PDF document text
    • https://cdn.sqhk.co/zodavujera/iasjbgd/loner.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4466140/normal_600f5bfa1f64d.pdfIn PDF document text
    • https://cdn.sqhk.co/fakosopalo/icOjbji/best_colouring_pages_for_adults.pdfIn PDF document text
    • http://ig-supportcenter.xyz/480278488921vymb.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4405179/normal_5fd958e84955b.pdfIn PDF document text
    • http://reduslim-officialsite.site/colon_cancer65g1s.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/427957ba-ab8a-4f50-a882-1fb2c6fff643/87502252102.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f45150da-31c9-402d-bdc2-0c4fd173f2c7/maths_basic_skills_worksheets_answers.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_off0000f7a2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7A2 5352 bytes
SHA-256: 798d82134cede77d6d9c56528ede93e65b69786096ba618fb15cd27d8e508b6c
font_01_sfnt_off000109f0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109F0 10300 bytes
SHA-256: 36f29289ec56f38eca6ce74833d3c7a4a3ce7cb552381e590501f5ebefd33dae