Malicious PDF — malware analysis report

Static analysis result for SHA-256 13681e43291db2ea…

MALICIOUS

PDF

76.0 KB Created: 2021-09-05 13:52:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: bec869c79b3d8f4fd23a2963f7f699fb SHA-1: 12b25c8f9e3189ac9cd6deb8cf14c028e7a8e69f SHA-256: 13681e43291db2eae3880529d78646f10ec17f156b65a7bc2f62395162e4ef86
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics as malicious, including a high-confidence ML classifier and ClamAV detection. It contains numerous links pointing to compromised WordPress sites and disposable hosting, suggesting a link farm designed to redirect users. The presence of these links indicates an attempt to lead users to malicious content, likely for phishing or to download further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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=encyclopedia+of+computer+science+and+technology+pdf+download PDF link annotation
    • http://mgocsm.in/userfiles/file/samutun.pdfIn PDF document text
    • https://www.vigo.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1608e104f26fdf---xifawomuruzenol.pdfIn PDF document text
    • http://kaplanpm.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cd5e8da8f25---1109271021.pdfIn PDF document text
    • https://www.letspassdriving.co.uk/wp-content/plugins/super-forms/uploads/php/files/vbvc1s7fkoe2kfm15q3dng1b4c/31774519343.pdfIn PDF document text
    • https://www.onestopnaturalstore.ca/wp-content/plugins/super-forms/uploads/php/files/jc3jrn2i7m99ua8gchh1kub372/7189993100.pdfIn PDF document text
    • http://theydeserveastamp.org/wp-content/plugins/formcraft/file-upload/server/content/files/1611685b73ad31---nexagisumifi.pdfIn PDF document text
    • http://www.advancedevents.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160c2974722a0e---xowexutijejafezepaja.pdfIn PDF document text
    • https://keluargamimpi2.com/contents/files/30583819315.pdfIn PDF document text
    • http://bydnjl.com/userfiles/files/96490815215.pdfIn PDF document text
    • https://hotelmitrutarija.com/uploaded/files/todexobe.pdfIn PDF document text
    • http://mirrorgallery.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609207d65f603---kuvitexogisoruwosukesowa.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606cc91ee3c95---87850387739.pdfIn PDF document text
    • http://rockpapersun.com/upload_mce_image/file/desuvasunarobadeva.pdfIn PDF document text
    • http://gokea.org/upload/editor/files/genefet.pdfIn PDF document text
    • http://iphonedown.com/ckfinder/userfiles/files/bezatafuxunaniwezebamid.pdfIn PDF document text
    • https://inchiriereelicoptere.ro/wp-content/plugins/formcraft/file-upload/server/content/files/161295c0e6f043---vowaroreziwimoviwofesi.pdfIn PDF document text
    • https://atcotourismtravel.com/userfiles/file/30461278280.pdfIn PDF document text
    • http://industra.sk/userfiles/file/17870720922.pdfIn PDF document text
    • https://robotics-institute.com/wp-content/plugins/super-forms/uploads/php/files/vtueedm6es383b9ei1bca47qmc/fajedekejafisakozogin.pdfIn PDF document text
    • http://ville-dammarie.com/ckfinder/userfiles/files/1532953090.pdfIn PDF document text
    • http://pcwenhua.com/uploadimg/file/16232200412001613547.pdfIn PDF document text
    • http://praconsulgroup.ru/pict/file/70566292751.pdfIn PDF document text
    • https://homeaestheticsllc.com/wp-content/plugins/super-forms/uploads/php/files/786d0cb00a7fd6e5e95f1d318c146b00/wixonovogomorezetadox.pdfIn PDF document text
    • http://studionegro.net/userfiles/files/70644175785.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_off0000c321.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC321 17392 bytes
SHA-256: b56fa52d34e4fca352e75363c2f1cc2a401f6fcb7b56230aac5b444746d2fa4d
font_01_sfnt_off0000ef8c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF8C 11352 bytes
SHA-256: 343c97c83734c375cf15d95bb63c418631a1601828eb9ac4451f4ef616dff547
font_02_sfnt_off000109eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109EB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1