Malicious PDF — malware analysis report

Static analysis result for SHA-256 82f38e6790ef2eee…

MALICIOUS

PDF

83.0 KB Created: 2021-09-11 22:53:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 42288076dbcd79a1a89500047a12126b SHA-1: 35bad5b4b2741ec1fe1229bdf091895cedf819da SHA-256: 82f38e6790ef2eeeae243eaf4455455fb1664e8b2e2cb71012c24acdfe825950
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as a phishing trojan and a machine learning classifier indicated a high probability of maliciousness. Heuristics identified the document as a link farm, with many URLs pointing to potentially compromised or disposable hosting. The presence of numerous external URIs suggests an attempt to redirect the user to malicious sites for further exploitation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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://xn--hjrnskadeakademien-mtb.se/userfiles/file/8063472533.pdf In PDF document text
    • https://globalcircle.club/userfiles/file/dobalirofinozi.pdfIn PDF document text
    • https://sitpchemcieszyn.pl/_sitpchem/file/jesudu.pdfIn PDF document text
    • http://thai-apsproducts.com/file_media/file_image/file/migogenobig.pdfIn PDF document text
    • https://bevillelecomte.ovh/ckfinder/userfiles/files/xasisogub.pdfIn PDF document text
    • https://vaitinhdien.com/app/webroot/upload/files/sobamozabasefimobeti.pdfIn PDF document text
    • https://dbhattacharjee.com/ckfinder/userfiles/files/1378522307.pdfIn PDF document text
    • http://uts.edu.co/portal/app/ckfinder/userfiles/files/89914612828.pdfIn PDF document text
    • http://paletydozahrady.cz/ckfinder/userfiles/files/wokivagidokiwevulen.pdfIn PDF document text
    • http://denge.aero/upload/files/pofoguginesipebilowe.pdfIn PDF document text
    • https://artofsurfing.com/preview/ckfinder/userfiles/files/17878136658.pdfIn PDF document text
    • https://leise.ru/admin/ckfinder/userfiles/files/lodivigoxafuwalanaxalixuk.pdfIn PDF document text
    • http://agilesolutions.in/uploads/49780231567.pdfIn PDF document text
    • http://sensor4you.com/fckeditor/editor/filemanager/connectors/php/fckeditor/upload/202109/file/kunitowijurasikazikoxug.pdfIn PDF document text
    • https://mygamedaysports.com/wp-content/plugins/super-forms/uploads/php/files/64bf43fab185f5e4fae82f8849f0bbd1/bokebikuxowimova.pdfIn PDF document text
    • http://probeg2000.ru/files/userfiles/files/towobax.pdfIn PDF document text
    • http://www.mueblesgamez.com/ckfinder/userfiles/files/xikinusimirixezi.pdfIn PDF document text
    • https://bcbc3399.com/upload/files/53485646341.pdfIn PDF document text
    • https://amagi.la/wp-content/plugins/formcraft/file-upload/server/content/files/1613c818a7a56b---35033336682.pdfIn PDF document text
    • http://studionegro.net/userfiles/files/gazijut.pdfIn PDF document text
    • https://monographie.com/ckfinder/userfiles/files/19182309503.pdfIn PDF document text
    • https://imapcb.org/wp-content/plugins/super-forms/uploads/php/files/678d12a59a97a4c81514b4038e2f94d9/43494335015.pdfIn PDF document text
    • https://landlorddebtadvisory.com/wp-content/plugins/super-forms/uploads/php/files/f9408060c7407daebd6c6c858e95c063/xasuputobopanipaxosufo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=android+phone+suddenly+turns+offPDF 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_off0000df10.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF10 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f722.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF722 18060 bytes
SHA-256: 9c0bde132203a430066a79cc5b4c7a717d0715d652741df9fc0e32f05c09a93b
font_02_sfnt_off0001264b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1264B 10628 bytes
SHA-256: ea8a57c3064daab6f669ed8ee696d9e5796ad619fdb1f1412275d13cfc86f1d0