Malicious PDF — malware analysis report

Static analysis result for SHA-256 bb35e7cf30266ae2…

MALICIOUS

PDF

83.6 KB Created: 2021-09-08 01:26:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 16ca34374ab5d6c865305933e3be480c SHA-1: 38b31d8e0825d8b006a5eaf6c89e3b6fb8dc034d SHA-256: bb35e7cf30266ae20df936d6dd447a06a9cddd7aa2d3f1453bacfc65762747d7
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress installations, indicating a link farm designed to lead users to malicious content. ClamAV and ML classifiers strongly indicate maliciousness, with the PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supporting the link farm nature. The primary purpose appears to be directing users to potentially harmful external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://lichnyiybrand.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1611cd92d1a9ea---75687358493.pdf In PDF document text
    • https://www.nordatec.com/wp-content/plugins/super-forms/uploads/php/files/ihn1cgje7abt5guc3b578i93hv/73470678037.pdfIn PDF document text
    • https://webhostmurah.com/wp-content/plugins/formcraft/file-upload/server/content/files/160832f3f48129---sebugirom.pdfIn PDF document text
    • http://jungvassar.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/pozanarudarelebute.pdfIn PDF document text
    • https://aduanaldelvalle.mx/userfiles/file/xekatukopokiz.pdfIn PDF document text
    • https://enville.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077907b01a95---96061367950.pdfIn PDF document text
    • https://nepalmicrofinancesummit.org/userfiles/files/bonowavexaluzetirivud.pdfIn PDF document text
    • https://www.fecomerciomg.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a3a1284ecd2---64971156859.pdfIn PDF document text
    • https://www.bountyvacation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b9877f5b207---gefazosexowifivo.pdfIn PDF document text
    • https://itracmediav5.com/ckfinder/userfiles/files/97518818189.pdfIn PDF document text
    • http://tavernadelsnoguers.com/wp-content/plugins/super-forms/uploads/php/files/e6af943890047747d17707696ec67c4f/tujuvuromigajugizuxiv.pdfIn PDF document text
    • https://hotellemaritime.com/hotel/upload/files/togedi.pdfIn PDF document text
    • https://www.officinadelgustoroma.com/wp-content/plugins/super-forms/uploads/php/files/cb73ba0a42bb1e6116a6b3e212452055/17138842035.pdfIn PDF document text
    • https://stalbeckers.nl/userfiles/image/file/60037923587.pdfIn PDF document text
    • https://qamarapps.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c08c0b057a2---xesekiwopugijo.pdfIn PDF document text
    • https://daulte.ch/ckfinder/userfiles/files/59751579047.pdfIn PDF document text
    • http://formel1vermietung.de/userfiles/file/79932883093.pdfIn PDF document text
    • http://songiadabinhphuoc.com/upload/ck/files/23823148057.pdfIn PDF document text
    • https://www.kasekimi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160843954b0ac0---tawupowapi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=tipos+de+maternidad+subrogada+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_off0000e020.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE020 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f837.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF837 11000 bytes
SHA-256: 2942c3aa7dce8ee816b56973b5085ee6ef05523988263f9b6feb0c08fb720a5a
font_02_sfnt_off0001115d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1115D 18424 bytes
SHA-256: 5b19dadd883a19a528ae2618916d66eebebde0a6da18a265aaa985318e826c5c