Malicious PDF — malware analysis report

Static analysis result for SHA-256 c3cf3dd11fc9b5ea…

MALICIOUS

PDF

71.8 KB Created: 2021-09-03 20:15:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 9d5a3de83cd3042caca8959a78c9a300 SHA-1: 140ca648ac331002e2146aa6069da4d2b36b38af SHA-256: c3cf3dd11fc9b5ea50fa921eb9a7dee2e24acab575ba307968e9db359416af08
156 Risk Score

Malware Insights

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

The PDF contains numerous links to various domains, many of which appear to be compromised or disposable hosting, indicative of a link farm. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or SEO abuse. No scripts were extracted, and the document body was unreadable, but the heuristic firings clearly point to a malicious link distribution pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://tandprotheses.com/ckfinder/userfiles/files/8096841834.pdf In PDF document text
    • https://ahi.com.ua/wp-content/plugins/super-forms/uploads/php/files/1c59cac8114030787e3cabffd19d8f2f/37899539065.pdfIn PDF document text
    • http://stopasbestos.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1607de6fe74de5---vajixajejanetarafitetilo.pdfIn PDF document text
    • http://aviatechinform.ru/sadm_files/58901324527.pdfIn PDF document text
    • http://likuidart.com/files/ckeditor/files/rugekumafawoxakubi.pdfIn PDF document text
    • http://www.abcklima.hu//data/editorfile/85090509046.pdfIn PDF document text
    • http://schnauzermountainminiatures.com/clients/17729/File/xexigimusalumem.pdfIn PDF document text
    • https://toppelletmachine.com/d/files/42643502150.pdfIn PDF document text
    • http://www.associatedomains.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab3d5a351ab---vegunokiposu.pdfIn PDF document text
    • https://desertflying.club/wp-content/plugins/formcraft/file-upload/server/content/files/160ae004f16f65---3239453584.pdfIn PDF document text
    • https://wisserarm.nl/app/webroot/files/userfiles/files/71850654290.pdfIn PDF document text
    • https://erinmillssmilesdentistry.com/wp-content/plugins/super-forms/uploads/php/files/bi8b5aejt790t9ld2dtjmj83l1/jakexijorifikivule.pdfIn PDF document text
    • https://c4ir.ae/wp-content/plugins/super-forms/uploads/php/files/29n2he247niiv68cgtg4jhu1s0/taveselenovetisezologes.pdfIn PDF document text
    • https://discoverapartmentsforrent.com/wp-content/plugins/super-forms/uploads/php/files/15ccb7b6cb7fa0bccceab6daad9801d9/84939059601.pdfIn PDF document text
    • https://dezsredstvompx.ru/wp-content/plugins/super-forms/uploads/php/files/148a11406cbd138cf7b85dd3774d37de/50003993928.pdfIn PDF document text
    • http://isystemlab.com/admin/ckfinder/userfiles/files/31335402114.pdfIn PDF document text
    • https://bucatariizidite.ro/printuri-fi/files/fekijomixaninepizuri.pdfIn PDF document text
    • http://ekbdrive.ru/ckfinder/userfiles/files/4915101588.pdfIn PDF document text
    • http://xiaohecollege.com/d/files/vixilebemuwa.pdfIn PDF document text
    • https://bluetact.com/ckfinder/userfiles/files/budikefetikiriwe.pdfIn PDF document text
    • http://jaatkinson.com/userimages/21767231385.pdfIn PDF document text
    • https://eijo.in/ckfinder/userfiles/files/14331389209.pdfIn PDF document text
    • http://compie.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1608077c4324e1---duforijelagusizigifu.pdfIn PDF document text
    • http://parkwestresidences.com/wp-content/plugins/formcraft/file-upload/server/content/files/160940aeb683ed---benopononone.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=all+right+now+chords+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_off0000b764.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB764 10672 bytes
SHA-256: 4f595bef06099dda314178c967ef79639433ed7ba18cdafd421cce2e1572f84e
font_01_sfnt_off0000cf93.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF93 16412 bytes
SHA-256: 4cbcfc3954ff0324da3f3361f9384efff874762fed17890b4c645305b0a7c40b
font_02_sfnt_off0000f9bd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9BD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1