Malicious PDF — malware analysis report

Static analysis result for SHA-256 39725fe6dec6d35a…

MALICIOUS

PDF

85.3 KB Created: 2021-09-06 00:38:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 296b074386cad986f51bf081ba0fbab0 SHA-1: 117c7dea4e955a55c98f18f97ce55802b031014e SHA-256: 39725fe6dec6d35a972835b391736bcec3eda3a7fad6f0dad1f6ad777b7ec6f1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a large number of external links, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly support its malicious nature. No scripts were extracted, but the structure and URL analysis are sufficient to determine the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://crystal-lamp.ru/uploads/files/tupuwizinitemazuruf.pdf In PDF document text
    • http://ongnuocdenhat.com/upload/files/48084977016.pdfIn PDF document text
    • http://sicompk.com/survey/userfiles/files/wojiweke.pdfIn PDF document text
    • http://xn--80aaae7amexjfdlfdfg.xn--p1ai/files/file/pukagimewuwiw.pdfIn PDF document text
    • http://victorylimo1.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f7b2799e775---nefefamule.pdfIn PDF document text
    • http://446888.top/userfiles/file/94107377467.pdfIn PDF document text
    • http://hk-bbc.com/upload/file/73483140968.pdfIn PDF document text
    • http://discoveryenglish.org/wp-content/plugins/formcraft/file-upload/server/content/files/16083bc773719b---biwukarefiroju.pdfIn PDF document text
    • https://oferta.lt/i/File/29634566729.pdfIn PDF document text
    • http://njuhome.pl/ckfinder/userfiles/files/tugafafawib.pdfIn PDF document text
    • https://eecpowerindia.com/codelibrary/ckeditor/ckfinder/userfiles/files/36247055951.pdfIn PDF document text
    • http://t-eamplus.de/web/editor/files/zegeduxivafefuwusefuki.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f8c4900881---jowusewa.pdfIn PDF document text
    • http://www.lightingandhvacexpo.com/wp-content/plugins/super-forms/uploads/php/files/beabe7e3c69d7f6510c524e7ba57b537/dagal.pdfIn PDF document text
    • https://www.swx.global/wp-content/plugins/super-forms/uploads/php/files/9e1236b51c599caa1254b1e73e2e061b/vevavaraked.pdfIn PDF document text
    • https://egyptsuntours.com/userfiles/files/27186011795.pdfIn PDF document text
    • https://lentes123.com/aym_image/files/tuvefupis.pdfIn PDF document text
    • http://www.goldenlantern.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160a7d0b1b393d---nexebivepexiven.pdfIn PDF document text
    • http://lesen-und-schenken.de/userfiles/files/15137549735.pdfIn PDF document text
    • https://micast.de/wp-content/plugins/super-forms/uploads/php/files/e3f9a3oejn0918342lj0ro35il/zemewidijedur.pdfIn PDF document text
    • https://sunridgecorp.com/uploads/files/202108241223269631.pdfIn PDF document text
    • http://ventmetal.ru/userfiles/files/sopolidawuperirexupexam.pdfIn PDF document text
    • http://splhardware.com/UploadFile/file/2021082109012973499.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=shuffleboard+table+plans+pdfPDF 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_off0000e7ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7FF 18200 bytes
SHA-256: 713fe0a18b4ce640ec574023c7633cbb2cf3e427aa92de2afb04d9a146e1c56e
font_01_sfnt_off000116d7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x116D7 10816 bytes
SHA-256: 89f6b355e096bd535028c17c137ccdf636d2927edb3e9b047e1f78e3966eac59
font_02_sfnt_off00012f85.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12F85 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1