Malicious PDF — malware analysis report

Static analysis result for SHA-256 7bad4edcf61e0912…

MALICIOUS

PDF

58.2 KB Created: 2020-11-10 02:31:41 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-14
MD5: cebf484513f5be5a92f418c8ccc0ad11 SHA-1: 81a9e35292968a42f0cee1e9db7e673582e2826f SHA-256: 7bad4edcf61e091262929b8238616651f495e7a4645e381becdd157730c19627
186 Risk Score

Malware Insights

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

The PDF file contains numerous external links, many pointing to disposable hosting services, suggesting a link farm or redirection scheme. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware delivery. While no scripts were directly extracted, the PDF structure and embedded URIs are indicative of techniques used to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://trafffe.ru/123?keyword=spanish+2+avancemos+textbook+pdf PDF link annotation
    • https://gefivepuli.weebly.com/uploads/1/3/4/6/134620723/zofinenirowawab.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4382412/normal_5f9a66f752dfb.pdfIn PDF document text
    • https://wetuxabo.weebly.com/uploads/1/3/0/8/130873937/xutovejiw.pdfIn PDF document text
    • https://noxazifegem.weebly.com/uploads/1/3/4/5/134596672/8913314.pdfIn PDF document text
    • https://topizamo.weebly.com/uploads/1/3/4/4/134435864/milojabixuxonu.pdfIn PDF document text
    • https://keniwuki.weebly.com/uploads/1/3/1/4/131483234/fibawubaxavuvabu.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/fosagoba/malulizulimumafas.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/209f1e34-298a-421c-a138-701d73ec3945/si_hacemos_un_mueco_acordes.pdfIn PDF document text
    • https://s3.amazonaws.com/jamokaroxoj/alphanumeric_symbol_series.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2114330f-7792-46e9-bc64-d7740d1da061/test_de_competencias_laborales.pdfIn PDF document text
    • https://s3.amazonaws.com/fofeguj/gas_and_sand_game_free_download.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_off0000a7d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xA7D6 5832 bytes
SHA-256: a7eb248937e1867412346ef9173cd92089e59f42c40ca8ce0db0c717372eec4b
font_01_sfnt_off0000bb98.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBB98 10008 bytes
SHA-256: 1f7e1370ca4ae13c6c803152f14e720cf501db431d9eee568e74f7ece847196d