Malicious PDF — malware analysis report

Static analysis result for SHA-256 a2d4fbe68f8bdbc2…

MALICIOUS

PDF

68.8 KB Created: 2021-09-05 20:06:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: a95c8a5a652edf3f281b4e58a1315358 SHA-1: d4185d7250a3fc750c701bb2e1a45adf9b1fc6c2 SHA-256: a2d4fbe68f8bdbc2d130806815a614aab9407669fd0e1f20498268737f1f2376
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links, many pointing to compromised CMS uploads or disposable hosting, forming a link farm. While no scripts were explicitly extracted, the PDF structure and heuristic firings suggest it's designed to lure users into clicking links that likely lead to further malicious content or downloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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 http://bellsazshihtzu.com/clients/878694/File/zulomigavoxotufuru.pdf In PDF document text
    • http://alumcity.ru/userfiles/file/nukarexafujubaw.pdfIn PDF document text
    • https://www.a2zmedical.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160ee659cc5abc---23034925884.pdfIn PDF document text
    • http://ichieh.tw/uploads/files/202108131535519636.pdfIn PDF document text
    • http://www.predoisiasociatii.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160834019c28a7---7226812525.pdfIn PDF document text
    • https://monyetmesum.com/contents//files/lojejeriw.pdfIn PDF document text
    • http://www.extramas.com/userfiles/files/20752926062.pdfIn PDF document text
    • https://raiporjai.com/piceditor/file/37930251909.pdfIn PDF document text
    • http://3e-recycling.ru/app/webroot/filesfiles/61869978644.pdfIn PDF document text
    • http://hondatayho.vn/images/ckeditor/files/22017296884.pdfIn PDF document text
    • http://fabtur.ru/upload/files/75547663788.pdfIn PDF document text
    • https://gresathouse.com/wp-content/plugins/super-forms/uploads/php/files/e15b6a33b3872af844230bc4019f637f/gejoxatoguxixegudez.pdfIn PDF document text
    • http://deasreunion.com/clients/860224/File/sorixeribo.pdfIn PDF document text
    • https://blackknowledge.com/wp-content/plugins/super-forms/uploads/php/files/9ca5e788dddbb899b1fd5ad83448bca8/45638909372.pdfIn PDF document text
    • https://amalighting.com/wp-content/plugins/super-forms/uploads/php/files/713635d5d02540ee97ea65185851971e/vexiso.pdfIn PDF document text
    • http://zavalinka.by/var/upload/file/monujixewidulezesot.pdfIn PDF document text
    • http://korsorlampang.net/user_img/files/tomawaw.pdfIn PDF document text
    • https://www.ezhealthcheck.com/wp-content/plugins/super-forms/uploads/php/files/egno853uq16bou824pm2urdia3/puxalugale.pdfIn PDF document text
    • https://www.yoursurveysurveyors.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607e5944ce9b8---59152853804.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=nested+classes+in+java+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_off0000b103.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB103 14628 bytes
SHA-256: af3b2d7d6141648c6c40f67da964acad013f1ac5edd10a54243dec20b7594ee5
font_01_sfnt_off0000d58e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD58E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000eda5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDA5 10568 bytes
SHA-256: f6cb5c11f7af3e931dfb1040663e71cc7efd94882ff579ea17d8a8a889974360