Malicious PDF — malware analysis report

Static analysis result for SHA-256 4acb4720ede027b8…

MALICIOUS

PDF

88.2 KB Created: 2021-10-11 07:59:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 567fcdc9d2c04c0489be13585da28a70 SHA-1: 5e21a2c3d6e4fbdb9acc5122e7eb8d2eecee96eb SHA-256: 4acb4720ede027b8a285db47e5c147c5d833c15f8565040e0aef2722561b1c22
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm or phishing lure. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or SEO abuse. No scripts were extracted, but the structure and URL patterns are indicative of a malicious document designed to redirect users.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9979

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://archism.ru/uplcv?utm_term=what+does+a+chest+tattoo+feel+like PDF link annotation
    • http://yuanhebiotech.com/upload/files/37379013908.pdfIn PDF document text
    • http://malir-naterac.info/UserFiles/File/41019787116.pdfIn PDF document text
    • http://gyarmatilovastorna.hu/userfiles/file/41841726118.pdfIn PDF document text
    • http://gs-metals.com/filespath/files/20210901141002.pdfIn PDF document text
    • http://edbiji.com/uploads/files/20210917232106_842583.pdfIn PDF document text
    • http://epmachine.ru/d/files/1378524251.pdfIn PDF document text
    • https://jin-hung.com/userfiles/file/74913388420.pdfIn PDF document text
    • http://swhos.com/upload/files/piwakusagowadad.pdfIn PDF document text
    • http://opalbiosciences.com/wp-content/plugins/formcraft/file-upload/server/content/files/161612c2f6a58c---jijebosujototedide.pdfIn PDF document text
    • http://qunjl.com/userfiles/files/fitenomopovamas.pdfIn PDF document text
    • http://www.hangmandigital.com/files/file/gojejedelababoram.pdfIn PDF document text
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/aa3ff379a283086a470c7150f5b906d4/pifunozigapowejila.pdfIn PDF document text
    • http://hermandadperdon.es/userfiles/file/54404623341.pdfIn PDF document text
    • http://purofirstli.com/userfiles/files/62312889709.pdfIn PDF document text
    • http://assisdrive.pt/userfiles/file/vugotifafato.pdfIn PDF document text
    • http://gespk.com/userfiles/file/22936395289.pdfIn PDF document text
    • http://avsa.org/sites/default/files/images/files/kevojirinidimiri.pdfIn PDF document text
    • https://rsun.pro/admin/ckfinder/userfiles/files/85908865606.pdfIn PDF document text
    • https://rosedreamholidayhomes.com/ckfinder/userfiles/files/zexexiv.pdfIn PDF document text
    • http://baozhaopharm.com/upload/files/vusedoruw.pdfIn PDF document text
    • https://hmjrgoldhockey.org/wp-content/plugins/super-forms/uploads/php/files/3afd777cf4c681398a0283e62b520909/xatejefodavojuvatuno.pdfIn PDF document text
    • http://hakanhurdacilik.com/userfiles/file/40295551580.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://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_off0000f0d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0D0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000108e7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108E7 10452 bytes
SHA-256: 2eb8dc30a580cc088ab01b21fa5185d6136fb9d40012cd40873b0d372eab16f6
font_02_sfnt_off000120c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120C9 19352 bytes
SHA-256: a7b923241bd50a4bd84f46587684e618988b8b3de92b01e449d48a00292b93a4