Malicious PDF — malware analysis report

Static analysis result for SHA-256 4372f104c285757f…

MALICIOUS

PDF

85.5 KB Created: 2021-09-06 06:55:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 800a4d867c3c4f809010babfa9b53aa8 SHA-1: 93131113c83926d976db8dcc75ffaea2052a20ff SHA-256: 4372f104c285757f38641178a9015d747b8fbf4eb03dbfecbc69f718e21d6db5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of embedded URLs, many of which point to compromised WordPress installations and disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or distributing further malware. No scripts were extracted, but the structure suggests a link farm designed to manipulate search engine results or redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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://yatros.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160e690316af44---6994950113.pdf In PDF document text
    • https://www.sabiamente.es/wp-content/plugins/formcraft/file-upload/server/content/files/16100cd0e337a2---gixigefawasalara.pdfIn PDF document text
    • http://www.hebrewforreadingcomprehension.com/content/ziwovokedezu.pdfIn PDF document text
    • http://www.icodar.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b245c72187d---17562755378.pdfIn PDF document text
    • http://thankschicken.com/uploads/files/bidemupuxitapekepax.pdfIn PDF document text
    • https://grandplaza.bg/uploads/assets/file/39824161384.pdfIn PDF document text
    • http://bjhtdszdh.com/v15/Upload/file/2021512180262398.pdfIn PDF document text
    • http://perfectthesale.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607100ede0f9e---33827128153.pdfIn PDF document text
    • https://holyfamilyhospitals.com/ckfinder/userfiles/files/66726629450.pdfIn PDF document text
    • https://melz-feu.ru/upload/fewiluv.pdfIn PDF document text
    • https://trongtrucsolution.com/uploads/files/mebijutawotelagu.pdfIn PDF document text
    • http://nek.ua/wp-content/plugins/formcraft/file-upload/server/content/files/1607d82bdea42b---21311429522.pdfIn PDF document text
    • https://jclifeschools.org/wp-content/plugins/super-forms/uploads/php/files/8d9667cb1ddd54bc1f6de9505fdd6f64/91757606678.pdfIn PDF document text
    • http://teckim.it/themes/userfiles//files/41232431302.pdfIn PDF document text
    • https://www.modianodesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/161153cbcc9297---5640811903.pdfIn PDF document text
    • https://bbensonmft.com/wp-content/plugins/super-forms/uploads/php/files/12bd2e75db210c9d105c1d9c623fd915/mosabefowoterubug.pdfIn PDF document text
    • https://www.tonygssoulfood.com/wp-content/plugins/super-forms/uploads/php/files/db342cf5aca2f6b0c1141a87ca1d8315/jatebojekosikejojagu.pdfIn PDF document text
    • http://aldara-latinoamerica.com/userfiles/file/77809587850.pdfIn PDF document text
    • http://stroynerud-sm.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16090b7054a412---rokuzunugupav.pdfIn PDF document text
    • https://www.lightingdynamics.com/wp-content/plugins/super-forms/uploads/php/files/2774d032adce43ee9191cac106aaebac/47108120160.pdfIn PDF document text
    • https://jbdclothiers.net/emailer/userfiles/file/nusajorogow.pdfIn PDF document text
    • http://fujavietnam.com/images/Download/sizejumipipotalevuvo.pdfIn PDF document text
    • http://hyeminshop.com/DATA/files/tozupap.pdfIn PDF document text
    • http://patriabrno.cz/userfiles/files/80460964458.pdfIn PDF document text
    • https://webhostmurah.com/wp-content/plugins/formcraft/file-upload/server/content/files/160878385dadaf---15735533002.pdfIn PDF document text
    • http://www.grupohk.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b8b94f7f383---tesakanonizutolipaner.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=conciencia+fonologica+actividades+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_off0000e39b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE39B 19580 bytes
SHA-256: ca096fbfd3ca0c938b430120af5b94b3a6d7448ed924ef9b116cee1ee405b03e
font_01_sfnt_off000115e8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x115E8 10792 bytes
SHA-256: fbbf595ed2dcfa3a706e3529b332ef2b8caa7cd0355d649a4c8d077405d3b699
font_02_sfnt_off00012ebd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12EBD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1