Malicious PDF — malware analysis report

Static analysis result for SHA-256 c21437fa0cead879…

MALICIOUS

PDF

86.4 KB Created: 2021-08-16 04:47:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 7e3880efb5a5f13857d6545a1c49512c SHA-1: 1f0c09624da5b7bd5f648c02c9bf099d072dcdd8 SHA-256: c21437fa0cead879c30b6948da7bd8328c59dc39f3fe0800094da79dd669d1ff
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links, many pointing to compromised WordPress sites, suggesting a link farm designed to redirect users to malicious content. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or malware delivery. While no scripts were explicitly extracted, the structure and URL patterns are consistent with a malicious PDF dropper.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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 http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606cb196e5ec4---87450318012.pdf In PDF document text
    • https://hoovermaids.com/wp-content/plugins/super-forms/uploads/php/files/e655b3630ab01109a5dcd7532aadb490/gabevojokevoxexukew.pdfIn PDF document text
    • http://cokhixnktientien.com/Images_upload/files/pexerasonazabaxol.pdfIn PDF document text
    • http://tradeweb.es/userfiles/file/61257496138.pdfIn PDF document text
    • http://danfilenemd.com/clients/67744/File/guzupub.pdfIn PDF document text
    • http://psychanalyste-gard.fr/ckfinder/userfiles/files/zasugijetisagalewuzege.pdfIn PDF document text
    • http://friluftsgruppen.se/wp-content/plugins/formcraft/file-upload/server/content/files/1608f4923005c2---ropakarinikiv.pdfIn PDF document text
    • https://useoneconvo.com/wp-content/plugins/super-forms/uploads/php/files/ccc812bc2a3cde76529084b74ba6a579/ladal.pdfIn PDF document text
    • http://franklinbristerharveyfamily.com/clients/a/a8/a8910385c57dfddac3c6311e2bd1422e/File/derudefixinebesasasexefa.pdfIn PDF document text
    • http://perfekttorun.pl/pliki/puled.pdfIn PDF document text
    • https://portugaliaimagyarok.com/ckfinder/userfiles/files/mevudasupum.pdfIn PDF document text
    • http://sb-78.ru/files/file/mefotojikekogajafurezaj.pdfIn PDF document text
    • http://www.virtualaid.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160a31721a052e---serogekokibosikigabiwed.pdfIn PDF document text
    • http://rocincorporated.com/domain.com/images/dynamic_pages/file/xedifokagogijuselu.pdfIn PDF document text
    • http://www.champcaregivers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8ba801139f---visokegakiwuresuvegu.pdfIn PDF document text
    • https://www.orthovision-lublin.pl/ckfinder/userfiles/files/62892564451.pdfIn PDF document text
    • https://tamtam.com.ua/wp-content/plugins/super-forms/uploads/php/files/302c7c74c9441690c0238c099a54a7fb/guligalidokopu.pdfIn PDF document text
    • http://lovec.bg/root/ckfinder/userfiles/files/tazunerudokamizatomosefut.pdfIn PDF document text
    • http://adbuilder.at/ckfinder/userfiles/files/31393552307.pdfIn PDF document text
    • https://3dreamstudios.com/wp-content/plugins/super-forms/uploads/php/files/59c102ecd500ff37042ada9eba75c0b9/begukivabupolumuwijusuja.pdfIn PDF document text
    • http://remont-elektro.eu/archiv/file/felipavujosewujugafefoni.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=2019+dodge+challenger+srt+hellcat+redeye+widebody+rwdPDF link annotation
    • 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_off0000eca8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECA8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000104ba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104BA 16784 bytes
SHA-256: e4342866a0af18cafbdc5710cdbed4aa3ba2118d8ea7a3de5277b2ab83dcbf3c
font_02_sfnt_off000130b1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x130B1 11356 bytes
SHA-256: 9c0916b4008e4f9ea11233de4dcb0f9965c335ec6b4ae35103808ec5a41a3a4f