Malicious PDF — malware analysis report

Static analysis result for SHA-256 21cdc09ae87dad8a…

MALICIOUS

PDF

83.9 KB Created: 2021-03-08 15:34:23 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-23
MD5: bdd0fbd1793f98619715dc5128e37749 SHA-1: 0ecfffaff94201bb5a2caafb7fd3a3ab3f014c84 SHA-256: 21cdc09ae87dad8a3aef73e0e06b55b3bc7458fa3efcc28cb8cd9bf5f75665bf
186 Risk Score

Malware Insights

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

This PDF file contains a large number of external links, many pointing to disposable hosting, suggesting a link farm or SEO spam campaign. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://resalured.ru/award?keyword=centrifugal+pump+price+list+pdf PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4368760/normal_6037e98437bb5.pdfIn PDF document text
    • http://bilkaita.space/english_to_spanish_dictionary_translationav9u1.pdfIn PDF document text
    • https://bavopasivivewid.weebly.com/uploads/1/3/0/7/130738836/kanid.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4369187/normal_601f7e40e1c22.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4393628/normal_5ff418e814d3c.pdfIn PDF document text
    • https://nubugudapo.weebly.com/uploads/1/3/2/8/132814946/a57eabf9.pdfIn PDF document text
    • http://cookwellbakewell.com/66088338938u1kji.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4391037/normal_6025e5d984023.pdfIn PDF document text
    • https://gitarufimoka.weebly.com/uploads/1/3/4/2/134235546/zovotefevasirave.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4487419/normal_60397291a97a1.pdfIn PDF document text
    • http://help-igcopyright.xyz/vilupachzas.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4385880/normal_5fe7be6bab2ce.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4471249/normal_5fe75b063f9a9.pdfIn PDF document text
    • https://danexuxubusam.weebly.com/uploads/1/3/2/6/132695747/a660cf.pdfIn PDF document text
    • http://shopmzm.site/persona_5_chanting_baboon8sgmt.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4458615/normal_602b7a2840e44.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4413696/normal_60383ed0055cc.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/7cbf3174-8f2a-4ca2-84ee-447a1198f436/bosch_nexxt_100_series_washer_will_not_spin.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a7229192-7943-4c6f-9ef6-cc69f55f1102/nipepezupilara.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/aeacf3e5-d1c4-40fb-80bc-586819ef8f61/lajiwusavavobeb.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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ec35.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC35 5380 bytes
SHA-256: 311486b8768b5c4c91201f3641c86682840c5f75d1669ca29db9fec16384b724
font_01_sfnt_off0000fe67.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE67 15016 bytes
SHA-256: 5804ade543ef9629ffe84dfe58da3e3d5b2befaf34cc6a3090319ca1e3bd2cda
font_02_sfnt_off00012d17.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D17 16164 bytes
SHA-256: c41fc46809d2260d2d1a821cef6bb00dae560fdbad380da94a93f29d012df54e