Malicious PDF — malware analysis report

Static analysis result for SHA-256 5c8099c93ae640c7…

MALICIOUS

PDF

75.7 KB Created: 2021-05-30 17:18:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: 11325fb9572942d3b09d364e1547443b SHA-1: a7b0ab82af4f4b7fcb5709999bd985be901c7c09 SHA-256: 5c8099c93ae640c72bd91d2a90668312dccb0d876a1ecdb52a48b1c4f0ef1ccb
186 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://seumenha.ru/strik?utm_term=financial+literacy+unit+3+test+answers PDF link annotation
    • https://fumunavizagoz.weebly.com/uploads/1/3/4/2/134235019/7aa1658933ae2.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4405443/normal_600f0aafa8e5d.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4490949/normal_60435086eb19c.pdfIn PDF document text
    • https://rutuwupu.weebly.com/uploads/1/3/1/3/131378820/6b2dd90cd761d22.pdfIn PDF document text
    • https://mezamelakinates.weebly.com/uploads/1/3/5/3/135304028/2531885.pdfIn PDF document text
    • https://wenabavur.weebly.com/uploads/1/3/1/3/131379405/sijobuk_nolelakilepis.pdfIn PDF document text
    • https://kujinorenut.weebly.com/uploads/1/3/4/3/134319997/punekifeweda-kefoxixasozoz.pdfIn PDF document text
    • https://pikowezapuxo.weebly.com/uploads/1/3/2/6/132681044/60c398.pdfIn PDF document text
    • https://wotipufa.weebly.com/uploads/1/3/1/0/131069738/pigoveladuzatu-poxozerakoj-wigipa.pdfIn PDF document text
    • https://xazatawivofudod.weebly.com/uploads/1/3/4/3/134313500/lunefana.pdfIn PDF document text
    • https://xujiwedebul.weebly.com/uploads/1/3/4/3/134317386/jiretebo_bivozimajejave_majilofetujejuv.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://uploads.strikinglycdn.com/files/241dfb36-7578-48db-aeaa-98a738b6cd29/4251200582.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f08a6b50-795a-4818-aee4-452308711290/return_of_service_form_georgia.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/16d231ff-0ccc-4b99-ab3d-0aa233ad5b03/secrets_of_the_baby_whisperer_espaol.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e014f6db-0ae3-42bb-9c37-26f5432a2909/lawixusazekelafubuloj.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9197628d-2fe3-4829-9195-9ab31343d89f/fisofuludanos.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/06b080bb-6bd5-47a1-82d4-ee8f5c84e1da/pitapa.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d35b7d67-e314-467c-b55b-3eae19917cc0/taking_sides_clashing_views_on_controversial_political_issues.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000db13.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB13 4880 bytes
SHA-256: 639d905c2a5ffce74cf1c739dc7a72418d77afd3f8bd2d0a00d88b6d29c809c1
font_01_sfnt_off0000ebbb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBBB 11120 bytes
SHA-256: df30b59f12567647865a5a500507254192b3abe436b7372229d46b43349654f1
font_02_sfnt_off0001119d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1119D 4324 bytes
SHA-256: a542ec26cea93e049a2e27cd59b1347dd9bbdea13775fd7b822b3c2b3136116f