Malicious PDF — malware analysis report

Static analysis result for SHA-256 678aec8c1b7906eb…

MALICIOUS

PDF

84.7 KB Created: 2021-09-05 15:32:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 493831af7e74a9f4cb0b03eced9b8fb9 SHA-1: 6528bf43a79ceb3693e5a2ad3bca96e7bfac4113 SHA-256: 678aec8c1b7906ebad5411d12940217a7a2a21bd1178aa312798966b66c7aac2
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress upload directories. Heuristics indicate this is a link farm on disposable hosting, designed to direct users to malicious content. ClamAV detection and ML classification confirm the malicious nature of the PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://steclotildehorton.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16091a7c059d8e---39211195755.pdf In PDF document text
    • https://assurancemauricie.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607df05c89188---fovazaxoxifenomu.pdfIn PDF document text
    • http://terapie-psi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1610c2cbc17b87---pebulogumelixirunutuj.pdfIn PDF document text
    • http://autosklo.sk/pictures/file/66056742276.pdfIn PDF document text
    • http://saamfactory.com/wp-content/plugins/super-forms/uploads/php/files/4ba871d05c44aadbda774d3ab2b7f1a3/joxorovezoduxesoninizo.pdfIn PDF document text
    • https://www.llgnjinc.com/wp-content/plugins/super-forms/uploads/php/files/55f6aea79177c861268733d4b1e8d86a/jovip.pdfIn PDF document text
    • http://moyamoya.center/images/hand_uploaded/files/80715830539.pdfIn PDF document text
    • https://pyhm.ca/wp-content/plugins/super-forms/uploads/php/files/ip34fme5a5odg841t41u90cr2o/66846593217.pdfIn PDF document text
    • http://recamonde.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160d70b18e17f3---16464285375.pdfIn PDF document text
    • http://rbtyutj01.com/userfiles/files/12709980506.pdfIn PDF document text
    • https://sk-developers.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610a5ef2ed2ef---wopuvaruxu.pdfIn PDF document text
    • http://www.jhannahs.com/wp-content/plugins/formcraft/file-upload/server/content/files/160909d89ba292---mevoxezalirefizifajewo.pdfIn PDF document text
    • https://padservhosting.com/userfiles/file/jegorivu.pdfIn PDF document text
    • https://ntct.dz/ckfinder/userfiles/files/56065410661.pdfIn PDF document text
    • https://chennothinterios.com/uploads/file/54170966115.pdfIn PDF document text
    • https://shared401k.com/wp-content/plugins/super-forms/uploads/php/files/276a9682e3231ab6c622b5d46b72c14a/54964144142.pdfIn PDF document text
    • https://jewfri.kr/files/image/files/44279533956.pdfIn PDF document text
    • http://stallingreunion.com/clients/a/a3/a37dbb3dca22f8cb40f44de83fe48269/File/26818815538.pdfIn PDF document text
    • https://primeodontorj.com/wp-content/plugins/super-forms/uploads/php/files/47baf2aef44e505c055fc2b3b813aa15/70189729706.pdfIn PDF document text
    • https://fiscalonline.eu/app/webroot/files/userfiles/files/xewapafabubijo.pdfIn PDF document text
    • https://chicagoportablexray.com/wp-content/plugins/formcraft/file-upload/server/content/files/160901e83cba45---86381991002.pdfIn PDF document text
    • http://jerseybankruptcylaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/jofalozulofalupujujotu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=handground+precision+manual+coffee+grinderPDF 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_off0000e45f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE45F 18116 bytes
SHA-256: 51bdaaa8c0b5c6b7fb95627680287936f0cbca623b269d17b87cab45f2aa539a
font_01_sfnt_off000113ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x113CA 10956 bytes
SHA-256: 01c38bc1d132a59020d1dee492272b0067855dca824449f7c809b88df8d97fbf
font_02_sfnt_off00012cdc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12CDC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1