Malicious PDF — malware analysis report

Static analysis result for SHA-256 9f71ba18ea4621d0…

MALICIOUS

PDF

84.9 KB Created: 2021-09-13 11:15:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 0be11943d3f850028446160ae76b4893 SHA-1: b89a8fa58a54816e57c514d964357aa8874cee87 SHA-256: 9f71ba18ea4621d0898da9a1f55e4d8d11d54f240b64d099c6f030548f713b1e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and a machine learning classifier indicated a high probability of maliciousness. Heuristics indicate the document functions as a link farm, pointing to multiple compromised CMS upload locations and disposable hosting sites. The embedded URLs suggest an attempt to direct users to potentially malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://www.videobezopasnost.ru/ckfinder/userfiles/files/92184014468.pdf In PDF document text
    • https://centar-znr-zop.hr/wp-content/plugins/formcraft/file-upload/server/content/files/161323d2dc64d6---buzopebilapamovudujibibe.pdfIn PDF document text
    • http://rbc-bezorgdiensten.nl/upload/duguxiguradikokul.pdfIn PDF document text
    • http://www.sparkprototypes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e8b4c965c0---farofegogujode.pdfIn PDF document text
    • http://aliceinformaticasrl.com/user/pages/87350552564.pdfIn PDF document text
    • https://118highschool.am/wp-content/plugins/super-forms/uploads/php/files/433520fe17c19fafccaf39868185efc3/bidavi.pdfIn PDF document text
    • http://herningbadintra.dk/app/webroot/upload/files/26448518259.pdfIn PDF document text
    • https://best-of-geldanlagen.de/userfiles/file/jurotiw.pdfIn PDF document text
    • https://dansobentre.net/uploads/file/22466922491.pdfIn PDF document text
    • http://dok-vo.ru/userfiles/file/5192013476.pdfIn PDF document text
    • http://xinyuemu.net/assets/202109/files/20210901091158298424.pdfIn PDF document text
    • https://greshamgilessalon.com/wp-content/plugins/super-forms/uploads/php/files/f6ff930c66155b4126bceff9d0648f67/dukujesalidonifi.pdfIn PDF document text
    • https://kitchensofdiablo.com/upload/file/24533988450.pdfIn PDF document text
    • http://www.maderas-navarro.com/ckfinder/userfiles/files/savobozipojiluseworut.pdfIn PDF document text
    • http://www.laterveer-biesenbeek.nl/ckfinder/userfiles/files/72305092751.pdfIn PDF document text
    • http://komputerzagrosze.pl/userfiles/file/kuxasokipuralus.pdfIn PDF document text
    • http://3t-t.com/User_File/UpFile/file/20210913115309_c2V6b3hlbmlwaXhpemFq.pdfIn PDF document text
    • https://dortmundpools.com/contents/files/rudikevevi.pdfIn PDF document text
    • https://thanaclusterwestgate.leaddeehub.com/userfiles/files/gafifoduri.pdfIn PDF document text
    • https://boucherienabli.com/uploads/FCK_files/file/zenegawej.pdfIn PDF document text
    • https://maria-galland.ru/files/file/butavutevi.pdfIn PDF document text
    • https://www.studioline.ie/ckfinder/userfiles/files/soxogigokonovoputaxovibu.pdfIn PDF document text
    • https://tpijobportal.com/ckeditor/ckfinder/userfiles/files/36113911065.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=does+instagram+lite+have+reelsPDF 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_off0000e7ee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7EE 17460 bytes
SHA-256: 03810a4583612c7445eae6d072b86bd9709c84d6ac51f7764f90b679b9e59d8a
font_01_sfnt_off0001157e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1157E 10624 bytes
SHA-256: ab4b9866088451d0d15c8e7239772358b13ab4453db98a1170ddc4d166c8461e
font_02_sfnt_off00012d96.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D96 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1