Malicious PDF — malware analysis report

Static analysis result for SHA-256 8d12802bccd5da35…

MALICIOUS

PDF

80.5 KB Created: 2021-09-07 19:17:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 5423e4a82288ad5c00e657a3948cb031 SHA-1: 49daa0244fd5e55dd9ff99f5b7718bb124e98b6d SHA-256: 8d12802bccd5da354fcf5ece8890deefe11ba77148c6f37c9ed0a369cd108136
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous links pointing to compromised websites and disposable hosting, suggesting a link farm or phishing lure. The presence of PDF-specific heuristics like 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' reinforces this, indicating the PDF is used to redirect users to potentially harmful content. Although no scripts were explicitly extracted, the nature of the links and the PDF structure suggest it's designed to exploit user interaction to lead them to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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 https://www.bluegreenshouseboats.in/wp-content/plugins/formcraft/file-upload/server/content/files/1610b7d15782cf---safiwigavevefi.pdf In PDF document text
    • https://www.18fire.com/wp-content/plugins/super-forms/uploads/php/files/f1b5c2653ed0704deac3c59b60b1d3f7/3787663050.pdfIn PDF document text
    • http://jagodkaprzedszkole.pl/userfiles/file/77718450905.pdfIn PDF document text
    • https://nhabe.com.vn/ckfinder/userfiles/files/zidifamig.pdfIn PDF document text
    • http://urparitet.ru/admin/ckfinder/userfiles/files/nabarux.pdfIn PDF document text
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/25100fa8678a285781a961f9d3515330/wefalerarewativenimelolir.pdfIn PDF document text
    • https://mamo-tato.ro/userfiles/file/5136527735.pdfIn PDF document text
    • https://www.sacproblemleri.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612655a3d33db---tojanu.pdfIn PDF document text
    • https://denizlihorozu.com/resimler/files/85173758429.pdfIn PDF document text
    • http://andreevmag.com/wp-content/plugins/super-forms/uploads/php/files/407f9407d6fd072f341c1671548c8d50/16176884015.pdfIn PDF document text
    • https://osakaav.com/userfiles/files/56935469630.pdfIn PDF document text
    • http://quickfix-poland.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098126206e93---saviwabedawabazulasulaz.pdfIn PDF document text
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/ob1v7vgf0f30s7fidk7dnuvej5/balopipidawafozovub.pdfIn PDF document text
    • http://aberdeeneyes.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607fe35515221---9330166110.pdfIn PDF document text
    • http://maginsaatmetal.com/resimlerfiles/47966163302.pdfIn PDF document text
    • http://amdind.com/userfiles/file/zaxukiranefevofalozunovi.pdfIn PDF document text
    • https://psfund.org/public/uploads/files/cms_files/55395684027.pdfIn PDF document text
    • http://jadever.vn/Images_upload/files/fedabidatigalirekelufij.pdfIn PDF document text
    • https://indiansabroad.uk/userfiles/file/zopirepejagew.pdfIn PDF document text
    • https://eurotig.ro/file/tusuvopikezazulotumi.pdfIn PDF document text
    • http://aldobini.it/userfiles/files/69426121939.pdfIn PDF document text
    • https://taevlingar.se/images/pages/file/53221944043.pdfIn PDF document text
    • http://sts-logistika.ru/wp-content/plugins/super-forms/uploads/php/files/d9142a427acf866bee74e23f0b5854f0/nubasefibibetataduxapo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=learning+shell+scripting+in+linux+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_off0000d51e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD51E 17788 bytes
SHA-256: aeaab71e9018e6bf83e7deec29c5c1845446c6f731de4052b886046e955fcc90
font_01_sfnt_off0001034c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1034C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011b63.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B63 10936 bytes
SHA-256: 2de502380b4e44871d43a13523e06a57157ce87b870b5651f70a2c746e522b1f