Malicious PDF — malware analysis report

Static analysis result for SHA-256 28c8dda771aa355a…

MALICIOUS

PDF

77.8 KB Created: 2021-05-13 12:01:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-14
MD5: 55ca33b3c59f8ed203ec2620b69ad801 SHA-1: 9d17ea733a36592e18226792ca559333122041e5 SHA-256: 28c8dda771aa355a144994f916e15cf810ca907c500ef91a80dba9baa939c72c
126 Risk Score

Malware Insights

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

The PDF contains an embedded URI pointing to a suspicious domain, identified by heuristics as a link farm on disposable hosting. ML classification and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. Although no scripts were extracted, the presence of a malicious URL suggests the document's purpose is to redirect the user to a harmful site.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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://dafemum.ru/strik?utm_term=classical+guitar+tabs+pdf PDF link annotation
    • http://gatofupimekow.mywebcommunity.org/brand_equity_questionnaire_sample.pdfIn PDF document text
    • http://taforojujutusig.mygamesonline.org/rizegikexe.pdfIn PDF document text
    • http://vevaxogejaz.scienceontheweb.net/pikurata.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4409092/normal_604fb9a483970.pdfIn PDF document text
    • http://xokezuwadem.mygamesonline.org/wofigeduxitizexok.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4448744/normal_603f8f2f63820.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/717ce1f2-8678-4656-8435-349b157d1768/la_metamorfosis_franz_kafka_numero_de_paginas.pdfIn PDF document text
    • http://vulebodifoguvar.epizy.com/dell_vostro_3568_spec_sheet.pdfIn PDF document text
    • http://girofili.myartsonline.com/99298972218.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f3a9ad9a-437a-47f9-ab7e-77de750987f6/nesibogikazubapadokule.pdfIn PDF document text
    • https://9de673a2-3b8e-40eb-bbf5-c0ad8e71a3da.filesusr.com/ugd/bd5c68_7e0d38ca2ba3487b96773b34b1d6f7db.pdf?index=trueIn PDF document text
    • https://caf0f927-206f-4b4e-aa34-0dd3da53679b.filesusr.com/ugd/83d902_0ddeaaf78b114058aef5ebbe139a4453.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/96f0a6be-9a5d-410a-86e9-d52e26ef4214/faxijofazupenenibemuged.pdfIn PDF document text
    • http://golorawubupub.rf.gd/gezeremoko.pdfIn PDF document text
    • https://a5fc3680-5c08-4cda-bd6c-abaa3bdf25bc.filesusr.com/ugd/ea5d7b_239deb6ee3ab4fc5a97d9480e79ed74a.pdf?index=trueIn PDF document text
    • https://b81e1767-bb0d-4562-9f98-cfef66859bb1.filesusr.com/ugd/b48b60_070710c5d52243bd80768adac45d3841.pdf?index=trueIn PDF document text
    • https://626fb5af-1d67-41cb-86ce-204163677ff0.filesusr.com/ugd/9d869b_86a33cf271544ae79d93c0e14baa7f04.pdf?index=trueIn PDF document text
    • https://67258aaf-84c5-4a88-bfd2-1aa7ddb6c27a.filesusr.com/ugd/850f07_d16808204d8c4570ba7aff57760b9322.pdf?index=trueIn PDF document text
    • https://a97be2a3-bfb5-42de-bba9-b145341b31aa.filesusr.com/ugd/1f2860_f3e081ae066c45cf8a132d0cfdd0b64c.pdf?index=trueIn PDF document text
    • http://gefuxexo.epizy.com/laughing_baby_video_clip_free.pdfIn PDF document text
    • http://lofukikusi.epizy.com/pejasaj.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9f55607f-6518-4de3-a407-e14516fa5398/actividades_de_escritura_para_segundo_grado_de_preescolar.pdfIn PDF document text
    • http://pitowurojagit.epizy.com/15469874608.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_off0000f12a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF12A 5368 bytes
SHA-256: 4cb5efd04a04a293680e7e5aa2e831ccc36fb896afbdeae0088ff9a3348d362d
font_01_sfnt_off0001036f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1036F 10840 bytes
SHA-256: 99dcb0ea1ff38be2b4a64cef0e1ff3e60106f9aa541f12c6e203c019dc42acff