Malicious PDF — malware analysis report

Static analysis result for SHA-256 fd4f4a439bfe95a2…

MALICIOUS

PDF

104.3 KB Created: 2021-08-05 13:34:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: e7da80806e903a2c19b316b18dae7ea5 SHA-1: ed7192dfc64982166de25c3767601dd16253f93d SHA-256: fd4f4a439bfe95a2798c40869556c3553269ebbe3a8be014702678e6e5de13f9
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains a large number of embedded URLs, many of which point to compromised CMS upload directories. The ML classifier strongly indicated maliciousness, and the structure suggests a link farm designed to manipulate search engine results or distribute malicious content. No scripts were extracted, but the overall pattern points to a phishing or SEO spam campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9989

Heuristics 5

  • 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://reiki-roots.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16087076d3c1a2---wiwifegufumepulokorilip.pdf In PDF document text
    • http://johnlillylaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/70074805769.pdfIn PDF document text
    • http://intechsol.kz/wp-content/plugins/formcraft/file-upload/server/content/files/160a9cfc5d83cf---96807562593.pdfIn PDF document text
    • http://aquatrustfina.com/userfiles/file/82919029990.pdfIn PDF document text
    • http://bizwd.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a7f3f0b78e9---90957776591.pdfIn PDF document text
    • http://aucoindeshalles.fr/menu/file/54038970031.pdfIn PDF document text
    • http://humanitool.ru/userfiles/file/14891533827.pdfIn PDF document text
    • http://orgue-chantepie.info/FCKeditor/upload/file/gotekanadefizizoramum.pdfIn PDF document text
    • http://etpatatietpatata.com/userfiles/files/nilafawixuzilo.pdfIn PDF document text
    • http://hoshitorionline.com/uploads/files/piguxajibigup.pdfIn PDF document text
    • http://blevy.com/ckfinder/userfiles/files/86666728019.pdfIn PDF document text
    • https://arenda1s.ru/wp-content/plugins/super-forms/uploads/php/files/3fe7a21b1094341b29d185d7f10b2902/13459327150.pdfIn PDF document text
    • http://copy2d.com/ftp/image/file/wedomorurebema.pdfIn PDF document text
    • http://www.drop-lok.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a9f6fccbee4---34124856497.pdfIn PDF document text
    • http://tuzvedo.hu/elemek/file/warumixuladedu.pdfIn PDF document text
    • http://www.ibadirect.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610a3cb5cd59e---zosilaponusuzazorer.pdfIn PDF document text
    • https://espaciocultivarte.com/ckfinder/userfiles/files/timojobevigavebozopu.pdfIn PDF document text
    • http://www.nowsingapore.co.id/wp-content/plugins/formcraft/file-upload/server/content/files/160d5541e256ec---79100089847.pdfIn PDF document text
    • https://rlmahtani.com/userfiles/files/77249296165.pdfIn PDF document text
    • http://aaaexpressac.com/userfiles/file/sewozovu.pdfIn PDF document text
    • https://terravistahometeam.com/wp-content/plugins/super-forms/uploads/php/files/dfb9affb1882749456c5ac7a1a7861e0/14578018071.pdfIn PDF document text
    • https://miamiuniquelimo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b6a24661d41---vazurumug.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=best+english+language+books+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_off000133fb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x133FB 11060 bytes
SHA-256: a28b058865b7abfed5ca9de20b52a5c758c2331bb764d5732d26c6bd6560b36e
font_01_sfnt_off00014d44.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14D44 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00016556.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16556 17412 bytes
SHA-256: a49295398b8fc70c2f19856fda628baf632569492a4855c8c3a00b09de3c17a1