Malicious PDF — malware analysis report

Static analysis result for SHA-256 da9782898a96b878…

MALICIOUS

PDF

75.5 KB Created: 2021-09-17 10:51:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 370dc6799e1330d6660ac122f6607b35 SHA-1: f258130690ec1234057e6e10178da9de6cdd973e SHA-256: da9782898a96b8786a45cfb1c439fddf43d101fb826d4c9405c18e8de18094fb
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF document contains a link farm pointing to numerous external URLs, many of which are PDFs hosted on compromised or disposable domains. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or malware distribution. The document's structure and URL patterns suggest it's designed to lure users into clicking through to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://mk-promotions.com/ckfinder/userfiles/files/nuxokafevomokazasarike.pdf In PDF document text
    • https://ln80.cn/filespath/files/20210911101111.pdfIn PDF document text
    • https://thehamptonsbloomington.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136043887cba---78348453204.pdfIn PDF document text
    • http://www.oomewatersport.nl/upload/files/vamev.pdfIn PDF document text
    • http://schodylux.pl/userfiles/file/46183854834.pdfIn PDF document text
    • https://sf-tfi-pgu.uz/wp-content/plugins/super-forms/uploads/php/files/8cdbbe6f6119706b1cdd4b6d21c28de0/nojufufefuwaduduwotukata.pdfIn PDF document text
    • https://miguktour.com/FileData/ckfinder/files/20210902_4CA182B564AA824E.pdfIn PDF document text
    • http://zoekidsworld.com/userfiles/file/51980701411.pdfIn PDF document text
    • https://sunwayhk.com/louis/STARKGROUP/ckfinder/userfiles/files/67574681827.pdfIn PDF document text
    • https://trongtrucsolution.com/uploads/files/56967771786.pdfIn PDF document text
    • http://apartamentykunickiego.pl/architekci/public/upload/ckfinder/userfiles/files/tafovosapafeduwilawitegu.pdfIn PDF document text
    • https://sporyolu.com/resimler/files/vesopifuromadol.pdfIn PDF document text
    • https://turismo-galicia.es/ckfinder/userfiles/files/41208396224.pdfIn PDF document text
    • https://truongthanhco.vn/webroot/img/files/81188431906.pdfIn PDF document text
    • https://ukmriptek.org/codeIgniter-hmvc/userfiles/files/webuvelutevasaf.pdfIn PDF document text
    • http://studiomilano.eu/userfiles/files/mopejidi.pdfIn PDF document text
    • https://irisapp.cn/uploadfiles/fckeditor/20210917/file/16318397419179.pdfIn PDF document text
    • https://windsbs.biz/files/file/63168219471.pdfIn PDF document text
    • http://cmuniontravel.com/userfiles/file/73114596277.pdfIn PDF document text
    • http://recruiters-zone.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ec901ea014---78846876297.pdfIn PDF document text
    • https://kuzeyilac.com/resimler/files/dojaxifufuxo.pdfIn PDF document text
    • http://coral-travel66.ru/admin/ckfinder/userfiles/files/62499730701.pdfIn PDF document text
    • http://angelojrobles.com/admin_initial_test/userfiles/file/73030432319.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=schaum%27s+outline+mathematics+of+finance+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_off0000c24b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC24B 17408 bytes
SHA-256: 53716c80b1269d3bcd4ace86aa4f1ca8370b8c61b6037c973d8bb709b9626192
font_01_sfnt_off0000eee8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEE8 10992 bytes
SHA-256: 6edea8c061e525d6b75c56f254820b89f5077c605f772a768df4392a0ccfcf61
font_02_sfnt_off00010846.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10846 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1