Malicious PDF — malware analysis report

Static analysis result for SHA-256 135c35ef39a4f8e6…

MALICIOUS

PDF

81.8 KB Created: 2021-09-17 18:05:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 3c5630fe493dca6ac7e39d7510d266c6 SHA-1: dee128c7dbb5bb8130c5aac719bca48971e54b79 SHA-256: 135c35ef39a4f8e673c7a23cf03fba15bfecbd03beb4183c66a653c97c01715a
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The sample is a PDF containing embedded JavaScript, which is often used to redirect users to malicious sites. Heuristics indicate it functions as a link farm, with many URLs pointing to potentially compromised or disposable hosting. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://urbanlivin.lu/userfiles/files/70048417572.pdf In PDF document text
    • https://360clothing.indicsys.com/home/www360cl/public_html/uploads/images/files/dajonagigokafi.pdfIn PDF document text
    • https://comodee.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614065a877dc2---96965884761.pdfIn PDF document text
    • http://tea-ra.com/user_data/upload/save_image/files/96965686967.pdfIn PDF document text
    • http://zaun-produzent.de/userfiles/file/28864600446.pdfIn PDF document text
    • http://utuin.net/files/fckeditor/file/11720380895.pdfIn PDF document text
    • http://mextro.de/upload/files/25851332076.pdfIn PDF document text
    • http://itkaufmann.com/images/fckimages/file/17941611878.pdfIn PDF document text
    • https://www.mtiwelding.co.uk/admin/ckfinder/userfiles/files/36939016805.pdfIn PDF document text
    • http://heilpraxis-pankow.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613ea7a350650---24575639146.pdfIn PDF document text
    • http://coutleelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/28427866720.pdfIn PDF document text
    • http://ewtch.com/upload/files/40926937693.pdfIn PDF document text
    • http://kayamedbursa.com/userfiles/file/577380213.pdfIn PDF document text
    • http://stacjaregeneracja.pl/userfiles/file/ledunujot.pdfIn PDF document text
    • http://dspec-car.com/js/upload/files/89512773503.pdfIn PDF document text
    • https://www.taxikladis.gr/wp-content/plugins/formcraft/file-upload/server/content/files/16140027060112---96661221150.pdfIn PDF document text
    • https://harpethvalleyhealth.com/wp-content/plugins/super-forms/uploads/php/files/b472c34fcc24f8184fd255ff1a2b839b/vovigiwugijoro.pdfIn PDF document text
    • http://plusk-car.com/js/upload/files/vavimasigenapedare.pdfIn PDF document text
    • http://bluebiz.kr/userData/board/file/bakejemezepunulegovaka.pdfIn PDF document text
    • http://dichvu12h.net/userfiles/file/zikasez.pdfIn PDF document text
    • https://elitteaccesorios.com/wp-content/plugins/super-forms/uploads/php/files/vkamoqp7l66mdgdtttt4j4br6f/74659359604.pdfIn PDF document text
    • http://jagatjyotischool.org/jagatjyotischool/userfiles/file/zofirorisirafetebugux.pdfIn PDF document text
    • http://waycreon.net/bhaskar/yii/upload/files/xumarakikov.pdfIn PDF document text
    • http://garankuccu.com/upload/fckimagesfile/f998bf6ea651e4de753bbd1f6dcf9411.pdfIn PDF document text
    • http://gammatradings.com/userfiles/file/fogaganevore.pdfIn PDF document text
    • http://jncs.kr/page_data/file/20210917170409.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=imperial+royale+gamePDF 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_off0000dbb7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBB7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f3ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3CE 10288 bytes
SHA-256: 5886fdc3e20067b6b085de39eee8fccbeb150b4aab29614120615235d5e58d15
font_02_sfnt_off00010ae7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10AE7 18308 bytes
SHA-256: 35a8d2d8539a2bc219d915ef7f664ed042da9ba7088f1381ada726d3b5537432