Malicious PDF — malware analysis report

Static analysis result for SHA-256 dd95557d92fb3f05…

MALICIOUS

PDF

69.8 KB Created: 2021-09-28 14:54:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 16743b71174d241ec2624c18e4f48ece SHA-1: 19f867f6dc8d395f7ad322503e392313f9ab0c17 SHA-256: dd95557d92fb3f059adeb52514c7fca1d7d72fef00fc26a607bb3a05694ffa83
156 Risk Score

Malware Insights

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

The PDF contains a large number of links, many of which point to compromised WordPress upload directories or disposable hosting, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly support the malicious nature of this PDF. The embedded URLs and the 'link farm' heuristics suggest the primary goal is to redirect users to potentially harmful websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9959

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 https://edarky.net/data/file/besepepimuxiworala.pdf In PDF document text
    • http://bk-plus.at/userfiles/files/21784820808.pdfIn PDF document text
    • http://chiangmai-esc.net/user_img/files/89538614874.pdfIn PDF document text
    • http://tauben-buchmeier.de/kleinberliner-schuetzen/userfiles/files/firewipowu.pdfIn PDF document text
    • https://impactmediaresources.com/userfiles/file/pavatevodurit.pdfIn PDF document text
    • http://www.pointcookelectrician.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16138215131ad5---21951925259.pdfIn PDF document text
    • http://www.multigacos.com/admin/uploaded/fck/file/tusasonadusevawug.pdfIn PDF document text
    • http://alpanelektrik.com/depo/sayfaresim/file/fikatixevigigitob.pdfIn PDF document text
    • http://udelimpa.es/ckfinder/userfiles/files/tebiralekodalo.pdfIn PDF document text
    • https://k-kompany.ru/wp-content/plugins/super-forms/uploads/php/files/2bc7c47b84134588444f1f8ffea39963/boxagenifesatujevoxibo.pdfIn PDF document text
    • http://joyear.com/ckfinder/userfiles/files/fekirutajaninepopolanaka.pdfIn PDF document text
    • https://izharfoster.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614297d0b4951---madomanonovekixom.pdfIn PDF document text
    • https://leganordavigliana.it/uploads/file/7737281404.pdfIn PDF document text
    • http://waxiangyuan.com/upload_fck/file/2021-9-6/20210906124837282919.pdfIn PDF document text
    • https://arichaindia.com/userfiles/file/sexawukupudilowapojube.pdfIn PDF document text
    • http://metabolit.ru/files/file/79645969181.pdfIn PDF document text
    • https://ccveg.org/wp-content/plugins/super-forms/uploads/php/files/gdbnrbk07hllcdoij82bv7vomi/wejivilu.pdfIn PDF document text
    • http://j-club.eu/userfiles/file/63735065352.pdfIn PDF document text
    • http://bellina.pl/userfiles/file/52257194403.pdfIn PDF document text
    • http://chikatere.com/Upload/files/boninutonuzaja.pdfIn PDF document text
    • http://mijneigenlift.nl/wp-content/plugins/formcraft/file-upload/server/content/files/161396a2463470---tajuxotekoguxozanafo.pdfIn PDF document text
    • http://vagtteam.dk/userfiles/Files/suboxu.pdfIn PDF document text
    • http://malopolskiszlakwinny.pl/upload/File/nirolenevusemetu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=best+one+piece+wallpaper+for+androidPDF 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_off0000af17.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAF17 15716 bytes
SHA-256: 51e4251d5d09876cf56b82bfd85a1df443468e885055b29bff5ccba1be008acd
font_01_sfnt_off0000d6ea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6EA 10752 bytes
SHA-256: d4085a4bea9cec227169af57b6ac386afa40c385e2ef74cc5eeaeb21598a195f
font_02_sfnt_off0000efe4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFE4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1