Malicious PDF — malware analysis report

Static analysis result for SHA-256 288ff88725e8f0b0…

MALICIOUS

PDF

67.9 KB Created: 2021-09-19 06:07:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 3187a43582b5c6090b8c646c0d1c4d2e SHA-1: 5c5c11e001b9f0b9f5c0ae77abd32dade84350c4 SHA-256: 288ff88725e8f0b083a77cddda72d2a7b30282b4f02d32bcfffbf61806e08ad6
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs, many of which point to potentially compromised CMS upload directories or are part of a link farm hosted on disposable domains. The ML classifier strongly indicated maliciousness. While no scripts were extracted, the structure and URL patterns suggest an attempt to lure users to external resources, possibly for further exploitation or SEO abuse.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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://wwm-quanta.com/upload/files/tenewip.pdf In PDF document text
    • http://trust-law-firm.com/userfiles/file/20210908192214_152330999.pdfIn PDF document text
    • http://matraholding.hu/images/userfiles/files/47190404442.pdfIn PDF document text
    • https://www.geosuiteonline.de/wp-content/plugins/formcraft/file-upload/server/content/files/16140d83f653ee---rafavoxosof.pdfIn PDF document text
    • https://granitnet.hu/editor_up/19112925332.pdfIn PDF document text
    • https://www.growxponential.com/wp-content/plugins/super-forms/uploads/php/files/9ph9q975k6e327ei6iicvb1qp5/80665045221.pdfIn PDF document text
    • https://theemperorsoldclothes.co.uk/wp-content/plugins/super-forms/uploads/php/files/bk7phcfk1pl2n8gij0lak5r9fd/gifipejaf.pdfIn PDF document text
    • http://yugang360.com/upload_fck/file/2021-9-14/20210914133748169497.pdfIn PDF document text
    • http://www.sg-callenberg.de/wp-content/plugins/formcraft/file-upload/server/content/files/16137c6b975401---75941671801.pdfIn PDF document text
    • http://lblussana.it/images/file/filuxuxifukujo.pdfIn PDF document text
    • http://grupomarsamo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131fc93b18ce---jugirumu.pdfIn PDF document text
    • http://avvocato-callegaro.it/public/file/nupawelutiduwemadibufimo.pdfIn PDF document text
    • http://officeharbor.com/pdtInfo/3318355123.pdfIn PDF document text
    • http://dautuck.com/uploads/userfiles/file/34193053047.pdfIn PDF document text
    • https://giltmorestukko.hu/ckfinder/userfiles/files/datepexo.pdfIn PDF document text
    • https://5703n1n6999-6a55.com/contents/files/29503307058.pdfIn PDF document text
    • https://steklo-shik.ru/userfiles/file/98999945720.pdfIn PDF document text
    • http://cserepakciok.hu/xdata/file/kikimetil.pdfIn PDF document text
    • http://karpatskiles.ru/store/file/fikuzex.pdfIn PDF document text
    • http://aloeverajuice.cz/files/file/laxezeweni.pdfIn PDF document text
    • http://zensushidanapoint.com/uploads/files/tudapokuxivapadadaziza.pdfIn PDF document text
    • https://jmtours.co/aym_image/files/gojuruzubawumowob.pdfIn PDF document text
    • http://kyochonbuenapark.iorderfoods.com/uploads/files/60916473469.pdfIn PDF document text
    • http://technimexvn.com/images/ckeditor/files/72795167529.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=suaraku+singing+app+downloadPDF 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_off0000ae1d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAE1D 14268 bytes
SHA-256: fbd03e434e50f9c1e28f71711a7935183b415f7abd595d8ee638a354b9c73116
font_01_sfnt_off0000d1d7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1D7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e9ee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9EE 10692 bytes
SHA-256: 46f444ed4b527bc30f097f4f600ad0ed0fa1ce8fc2ee5d04117ce3698861ff80