Malicious PDF — malware analysis report

Static analysis result for SHA-256 104fd92b4a1c5301…

MALICIOUS

PDF

74.5 KB Created: 2021-06-10 14:53:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: 6894285a8f200a5e773e9fd9023c99e2 SHA-1: 0a80349e0c2f1f66bd7c2f4ec38d913d1cf45dd1 SHA-256: 104fd92b4a1c5301a6f5ae43ee1ac675ca7811ca2f95bed1869fddcccca497a6
126 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, with the primary one being `https://garglob.ru/pbw?utm_term=2+kids+and+1+sandbox`. The heuristic `PDF_SEO_DISPOSABLE_LINK_FARM` indicates the PDF is designed as a link farm on disposable hosting, suggesting a phishing or malware distribution scheme. No scripts were extracted, but the overall structure points to a malicious document likely delivered via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 5

  • 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 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://garglob.ru/pbw?utm_term=2+kids+and+1+sandbox PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4450721/normal_601e5cce02b47.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4419410/normal_601afe19d3196.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4425483/normal_5fdca8d2cd62d.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4474722/normal_6014c0c18519f.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4369509/normal_601f6a00a2c39.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4459788/normal_600a05c01f789.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4467564/normal_60097c8f8f5f1.pdfIn PDF document text
    • https://static.s123-cdn-static-d.com/uploads/4366313/normal_60b47aa4a4760.pdfIn PDF document text
    • https://static.s123-cdn-static-d.com/uploads/4445101/normal_60b12d9326304.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4370068/normal_604165e838ed6.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4462993/normal_5fd3abf9cc8be.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4383304/normal_60422206e848a.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4455673/normal_60bcd0df23fad.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4492588/normal_6007ec9ad59f7.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4458388/normal_600b902a6cffc.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://pefumugat.pbworks.com/w/file/fetch/144595164/95537517676.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/be41df24-6e79-44ba-8cc7-0d55f460dbbf/samsung_frame_55_inch_specs.pdfIn PDF document text
    • http://dagomiwavi.pbworks.com/w/file/fetch/144918552/xadibajuxa.pdfIn PDF document text
    • http://jopamedet.pbworks.com/f/how_much_can_a_ford_ranger_tow.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/796ab423-94eb-47d0-abac-98eac5324502/compare_and_contrast_war_of_the_worlds_book_and_movie.pdfIn PDF document text
    • http://wenitat.pbworks.com/f/wiwugobisotapisaxisupisem.pdfIn PDF document text
    • http://gaguseka.pbworks.com/f/how_to_fix_lg_washing_machine_oe_error.pdfIn PDF document text
    • http://wekibivu.pbworks.com/w/file/fetch/144657264/guwurobesamidalawabo.pdfIn PDF document text
    • http://vejivab.pbworks.com/f/47409408010.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_off0000e455.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE455 5052 bytes
SHA-256: a187f74a9e0a5faa2fc85efcd6874882f79f6c5bbf455d9dbae6e4a3c5b9c526
font_01_sfnt_off0000f59e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF59E 11044 bytes
SHA-256: 4f280a2c2e2db9bfcca433500864703810c6109c7ffc98c118639ca19bb02dad