Malicious PDF — malware analysis report

Static analysis result for SHA-256 bf89882b9a573620…

MALICIOUS

PDF

99.3 KB Created: 2021-09-06 09:01:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 104ed33722969919068be92e17718128 SHA-1: 7d072083a48c16b9a591bcaa48fdbe746ed838c7 SHA-256: bf89882b9a573620f5d9398545103f5bf0c6077c2ec7fe0c83f23c0870e5af71
96 Risk Score

Malware Insights

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

The sample was identified as malicious by an ML classifier and exhibits characteristics of a link farm. It contains numerous URLs pointing to PDF files hosted on various domains, some of which appear to be compromised CMS upload directories. The primary purpose seems to be redirecting users to potentially malicious content, aligning with phishing or malware distribution tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

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 https://www.loisirs-auto-occasion.fr/ckfinder/userfiles/files/84121292418.pdf In PDF document text
    • http://konstruktor33.ru/app/webroot/files/files/towirigegalerej.pdfIn PDF document text
    • http://ukonlinedirect.com/userfiles/files/bibanedufofetum.pdfIn PDF document text
    • http://herculesestateplanning.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/korojoxodulaguminireros.pdfIn PDF document text
    • https://canevastoilestjean.com/upload/editor/file/lekobadososejamumevikano.pdfIn PDF document text
    • http://reiki-roots.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1610a71125eea0---28594246225.pdfIn PDF document text
    • http://geraldkleinlaw.com/ckfinder/userfiles/files/dizumegotomawonate.pdfIn PDF document text
    • https://shindah.com/images/ckeditor_img/files/wokawixisozametusoladas.pdfIn PDF document text
    • https://shinyjewellers.com/wp-content/plugins/super-forms/uploads/php/files/lc3qvfssj1l43t000tjoeie54v/tezuzetonexuvavuwuseje.pdfIn PDF document text
    • https://veritiesinstitute.com/wp-content/plugins/super-forms/uploads/php/files/e6ce582799ff36a3e23120ead6bc007c/wozopat.pdfIn PDF document text
    • https://www.finestkindcharter.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b37f5fb827a---repakedori.pdfIn PDF document text
    • https://www.msolartop.cz/wp-content/plugins/formcraft/file-upload/server/content/files/16094acdcbec2e---xoxafanuzu.pdfIn PDF document text
    • http://suachuaspa.com/upload/images-content/files/xeraduxilemixinefelexeles.pdfIn PDF document text
    • http://www.dnevi-sekretarjev.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1607c36681a24d---topadatisupo.pdfIn PDF document text
    • http://kehlux.lu/userfiles/files/fosaxibalaborusasufulug.pdfIn PDF document text
    • https://smarttactic.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160aae21258fb2---doxomubiwakalito.pdfIn PDF document text
    • https://sharidendesignasphalt.com/wp-content/plugins/super-forms/uploads/php/files/105ceef98d035d7d9e174a0d6b4fc7b8/3914708118.pdfIn PDF document text
    • http://boldogelet.hu/media/vomijikizunutalagapixek.pdfIn PDF document text
    • https://master.plus/wp-content/plugins/super-forms/uploads/php/files/bc897adb5d2cbbcc3a2153f0a1b6c381/29209410991.pdfIn PDF document text
    • https://ceilford.org/wp-content/plugins/super-forms/uploads/php/files/a111713eeb7ed09f61ef9dcb8d909ff3/22129349196.pdfIn PDF document text
    • https://levin-dent.ru/wp-content/plugins/super-forms/uploads/php/files/e6c422965e1b752e839b9546c606c642/41219001824.pdfIn PDF document text
    • http://kaitosushisb.com/uploads/files/83748062793.pdfIn PDF document text
    • http://jncs.kr/page_data/file/20210610101557.pdfIn PDF document text
    • http://kapalishakti.com/ckfinder/userfiles/files/robox.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=visualizar+pdf+con+javascriptPDF 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_off00011ba3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BA3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000133b5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x133B5 19204 bytes
SHA-256: 90cac570589b0024f1fd17f57cc5d68315525987b393b68dbe1dd452c4e977bc
font_02_sfnt_off00016621.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16621 10804 bytes
SHA-256: 3f5d46b862c334f233d2474a1606525869f03b31602306bb6ba9fce1b3bfdcca