Malicious PDF — malware analysis report

Static analysis result for SHA-256 456a0df36d26d5c7…

MALICIOUS

PDF

83.3 KB Created: 2021-09-06 01:17:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: d04b982dbee22c8f9dcc680491addbc0 SHA-1: a9ce774733c666f28843d062fc9f700d2f666a53 SHA-256: 456a0df36d26d5c72c35e25c1b1cb39e1219f9ab5be0cf605af54561146ecfb8
204 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The file functions as a link farm, directing users to various compromised WordPress upload sites and disposable hosting domains, likely to facilitate the download of a secondary payload. The presence of 'wkhtmltopdf' in the metadata suggests it was generated by a tool, potentially to obscure its true nature or to create a deceptive document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9911

Heuristics 8

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • LOLBin token sequence in document text high SE_LOLBIN_RUN_COMMAND
    Extracted document text contains a Windows script/execution tool name (PowerShell, mshta, cmd, rundll32, regsvr32, …) within 220 characters of a dangerous flag, command verb, or URL. This is a visible 'run this' instruction in HTML/PDF/RTF lure bodies, or — in macro-laden Office files — the macro's own string-pool entries appearing adjacent in extracted text.
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://euredit-editions.com/userfiles/file/kajavijuvovi.pdf In PDF document text
    • https://askopenko.com/wp-content/plugins/super-forms/uploads/php/files/6511724c8433ec7d6232fc91b4676483/zezufil.pdfIn PDF document text
    • https://fermuar.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bef9d37272b---47915748334.pdfIn PDF document text
    • https://stewsites.com/wp-content/plugins/super-forms/uploads/php/files/ec880b24e049b352bddab6ee3a927b7a/17465789485.pdfIn PDF document text
    • https://cityface.cz/res/file/33805942153.pdfIn PDF document text
    • http://kwik-it.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16111e2c2b681c---87172288668.pdfIn PDF document text
    • https://immobiliaresancarlotrieste.it/file/73520653255.pdfIn PDF document text
    • https://urbanlivin.lu/userfiles/files/36857512969.pdfIn PDF document text
    • https://careersourceokaloosawalton.com/files/public/sadolixomubanuvesej.pdfIn PDF document text
    • https://gomaihoa.net/upload/files/tosesemekiba.pdfIn PDF document text
    • https://svetpoznaniyaonline.ru/wp-content/plugins/super-forms/uploads/php/files/6b616467b036d4bde071cbea8b5d653f/xazirezakasizuje.pdfIn PDF document text
    • http://www.bridalchapel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160acdbd72ede3---kivofobisegesafaxiwe.pdfIn PDF document text
    • http://www.meglobalinc.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160ccef5fb9f4b---58278771903.pdfIn PDF document text
    • https://livingcircles.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160b54c09d3f06---12887605112.pdfIn PDF document text
    • https://tfnd.org/wp-content/plugins/super-forms/uploads/php/files/2d5ea86b93f6e5d2610f9af9b86c9a97/18997534753.pdfIn PDF document text
    • https://humanistbeauty.com/wp-content/plugins/super-forms/uploads/php/files/gkdef4bkdufvdjaj6qrtkbunfq/42095698745.pdfIn PDF document text
    • http://beetsom.com/PROGRAM_FCKeditor_UserFiles/file/399870450609e120dd0981.pdfIn PDF document text
    • http://pck.malopolska.pl/wp-content/plugins/super-forms/uploads/php/files/ab370f9d03a48a3b8e73d1222bcfbe52/92118017015.pdfIn PDF document text
    • https://action-roofing.com/wp-content/plugins/super-forms/uploads/php/files/c465ac4cc43fbd43aef0d7c8f67c99f1/bewop.pdfIn PDF document text
    • https://rtvpuls.com/ckfinder/userfiles/files/92249326817.pdfIn PDF document text
    • https://kalatranslation.co.uk/wp-content/plugins/super-forms/uploads/php/files/g6hgvntnmif74kin1f94g0q5sb/viwurigixajifebogeba.pdfIn PDF document text
    • https://gmonlinestore.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e1e617bb0a---19012206285.pdfIn PDF document text
    • http://www.naturapreserved.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609097251c4b9---silutupobitaxited.pdfIn PDF document text
    • https://fiberglasssupplydepot.com/userfiles/file/xagojojiketimubewenapaxa.pdfIn PDF document text
    • http://charmingcurls.se/upload/file/zonifepirom.pdfIn PDF document text
    • http://open.ua/uploads/ckeditor/files/50078260875.pdfIn PDF document text
    • https://www.twibiotech.com/plugin/ce1/ckfinder/userfiles/files/56771984449.pdfIn PDF document text
    • http://open.ua/uploads/In macro / runtime command snippet
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=sourcing+and+procurement+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_off0000e0a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0A3 10924 bytes
SHA-256: 1e33b5fa13675639fc953b9099b9afd43c553337d0f490742a3c99aa19079677
font_01_sfnt_off0000f9c2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9C2 17748 bytes
SHA-256: 4dcef45cc9f4b12c403fa9c1f9310961d31e68c6dc17c7b48faee0caaf4c5b62
font_02_sfnt_off000126fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x126FC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1