Malicious PDF — malware analysis report

Static analysis result for SHA-256 58f9f3798fc3566d…

MALICIOUS

PDF

81.9 KB Created: 2021-09-12 23:21:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 6defaad7537b6cc466b9528ea3cd51a9 SHA-1: a12760fadb270da311c53c712497c6fe3ef1b7d1 SHA-256: 58f9f3798fc3566d23dd2c77090ad1d8ff9103e7fb9616828d9196bf0733023c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of external URIs and link farm heuristics, indicating it's designed to redirect users to potentially malicious websites. ClamAV detection and ML classification confirm its malicious nature. While no scripts were explicitly extracted, the PDF structure and numerous URLs suggest it's part of a phishing or malware distribution campaign, likely initiated via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://catamma.ru/uplcv?utm_term=periodic+table+class+11+pdf PDF link annotation
    • http://embody.box8websites.com/ckfinder/userfiles/files/razujixu.pdfIn PDF document text
    • http://dioceseofniranam.org/userfiles/file/rujanu.pdfIn PDF document text
    • http://thermcom.cz/userfiles/file/74792639957.pdfIn PDF document text
    • https://k9-warrior.com/wp-content/plugins/super-forms/uploads/php/files/qmu5tsf3ss6nim4iqja06n6pva/23703203889.pdfIn PDF document text
    • http://calisnt.com/uploads/files/kuwimem.pdfIn PDF document text
    • https://radekslodkiewicz.pl/files/file/65924938308.pdfIn PDF document text
    • http://www.mmalappeenranta.com/tiedostot/files/kuritutogovefejod.pdfIn PDF document text
    • http://songhakbbq.com/uploads/files/41069583243.pdfIn PDF document text
    • http://mitroc.com/userfiles/file/2668657419.pdfIn PDF document text
    • http://nnk.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1613c523e74ca7---mazunawafag.pdfIn PDF document text
    • https://ags-car.60km.com/upload/files/zenexixidunaneworejo.pdfIn PDF document text
    • http://vdgairconditioning.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16135d81fe5052---kojawabamovisulolowur.pdfIn PDF document text
    • http://ciarajewellery.com/editor_upload/file/66933115678.pdfIn PDF document text
    • http://worshipedia.mobi/sites/default/files/file/83591873103.pdfIn PDF document text
    • http://www.sandipmallick.com/fckimages/file/37631366254.pdfIn PDF document text
    • http://fullcolorspandoeken.nl/userfiles/file/nufilusejomo.pdfIn PDF document text
    • https://eledigitalpr.it/allegati/file/45125449971.pdfIn PDF document text
    • http://cnzhongkui.com/fckeditor/editor/filemanager/connectors/php/uploads/file/082309344642.pdfIn PDF document text
    • https://www.food-equipment-store.com/fckeditor/uploads/file/23026590679.pdfIn PDF document text
    • http://studiotecnicomartani.eu/userfiles/files/14907107691.pdfIn PDF document text
    • https://ksmt.edu.np/assets/ckfinder/userfiles/files/mukuru.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_off0000db83.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB83 10700 bytes
SHA-256: 4de68d9104862c932a45080d70e9c674c7811152f88d3b06e9d9d6f0e5a676d3
font_01_sfnt_off0000f401.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF401 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010c13.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C13 17804 bytes
SHA-256: 8645d8f23b8be6efacfd36e2e672fddc4f255e11f7351f997d12b839a726b473