Malicious PDF — malware analysis report

Static analysis result for SHA-256 4333b694eecadd5a…

MALICIOUS

PDF

84.5 KB Created: 2021-09-21 05:32:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 71d2193bf5a8ad11a393deee9e6a5579 SHA-1: 47239f3df1942cc500e9443ea021b05d256fe6b8 SHA-256: 4333b694eecadd5abb6c96d58e34992e395d545fcf4cabd2eb73ecf973c1ec32
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which are hosted on disposable domains or compromised WordPress sites, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution through these links. The document body was unreadable, but the heuristic firings clearly point to a link farm attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://coretry.ru/uplcv?utm_term=open+oreo+tv PDF link annotation
    • http://autosoftware.company/autoresponders_images/files/8468508030.pdfIn PDF document text
    • http://tao-oita.com/admin/upload_filesfile/zabibexupulowi.pdfIn PDF document text
    • http://winhazel.com/indigo/ckfinder/userfiles/files/romikofipefafe.pdfIn PDF document text
    • http://www.kevinbrooks.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1613ee96c2106b---7008315505.pdfIn PDF document text
    • https://ateliersmq.com/pevron/www/img/file/xebexusuwekutujexegibiraz.pdfIn PDF document text
    • https://www.asoriofrio.org/ckfinder/userfiles/files/kilonapenezizupiroz.pdfIn PDF document text
    • https://hogies.com/includes/template/uploads/file/potuzevulikisexutufawi.pdfIn PDF document text
    • http://mascotdd.com/file_media/file_image/file/25602061206.pdfIn PDF document text
    • http://rayer.cn/d/files/pigokuzatelegofitel.pdfIn PDF document text
    • http://gocchame.vn/app/webroot/img/uploads/files/wubavisovebowuxinamarowa.pdfIn PDF document text
    • http://ifaistos.reality.gr/~triantaf/images/file/41904267136.pdfIn PDF document text
    • http://benrassam.com/uploads/files/53626759694.pdfIn PDF document text
    • http://propertiesforrent.com/userfiles/file///bamagemoru.pdfIn PDF document text
    • http://gibisch.org/files/files/38685712192.pdfIn PDF document text
    • https://autosofortkauf.ch/wp-content/plugins/super-forms/uploads/php/files/h65csgs2n364s7npbnlh6lmfc5/vimomasafodow.pdfIn PDF document text
    • https://chocoinmobiliario.com/wp-content/plugins/super-forms/uploads/php/files/dee5291eac3e883a69b4dc263fddede6/73369106375.pdfIn PDF document text
    • http://hepiran.com/cache/fck_files/file/80690358322.pdfIn PDF document text
    • http://xn--80aejmo0alc.xn--p1ai/ckfinder/userfiles/files/25692885806.pdfIn PDF document text
    • http://stacjaregeneracja.pl/userfiles/file/9771612571.pdfIn PDF document text
    • http://ericshartman.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/40475499069.pdfIn PDF document text
    • https://benhgout.net/uploads/Files/file/fikewefazojiwima.pdfIn PDF document text
    • http://goref.ru/files/file/75966640984.pdfIn PDF document text
    • http://agataklimowska.pl/userfiles/file/liwaxoteminugexi.pdfIn PDF document text
    • http://teleserviciomalaga.com/ckfinder/userfiles/files/velupolujipugagi.pdfIn PDF document text
    • 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_off0000e6c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6C6 18768 bytes
SHA-256: 4702e45f5cd3f1bfc57ed4e4f0dc7d9aa2867cda4deb8c3135de6756b06fb32f
font_01_sfnt_off00011742.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11742 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012f58.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12F58 9868 bytes
SHA-256: 062d716d637a7abe4da7ff7a1efc6b47736f0e3b7538dd755a308e92380ffac4