Malicious PDF — malware analysis report

Static analysis result for SHA-256 9223a15ce815adbd…

MALICIOUS

PDF

85.9 KB Created: 2021-07-03 18:41:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 53e5fe3d6f289fe2221a86de58614160 SHA-1: 20776afc590498b9e10997ee923aba84634fde75 SHA-256: 9223a15ce815adbda8e30f0fbb827c49784a70db5453c4ddfcb37499a888cab5
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 User Execution: Malicious File

The PDF document contains a link farm pointing to numerous compromised WordPress sites, which in turn host other PDF files. This suggests a multi-stage distribution or phishing campaign. The ML classifier strongly indicated maliciousness, and the structure of the PDF points towards an attempt to lure users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

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://laxmigrouppune.com/wp-content/plugins/super-forms/uploads/php/files/25278b5c0e81517cd7fc1cc257f99698/keriwugetibometujuxobe.pdf
    • https://himalayanwanderer.com/himalayan/userfiles/files/56369983282.pdf
    • http://delawaretravelmedicine.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607216cd4e77b---30162271112.pdf
    • http://dishandspoonproductions.com/ckfinder/userfiles/files/ziwip.pdf
    • http://viaterrestre.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a6d2ca0fca5---12752238720.pdf
    • https://luminex.pl/upload/file/23017170501.pdf
    • http://kimyasaldubeller.com/upload/ckfinder/files/96798780816.pdf
    • http://www.tif.cn/wp-content/plugins/super-forms/uploads/php/files/4ht5622vh1rnrbg372afoajk09/79408502886.pdf
    • http://accessprecision.com/userfiles/file/52550055153.pdf
    • http://countrysquirefoods.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a82794e3b4d---64844859153.pdf
    • https://bioesteticaonline.it/file/kirumekagajibefatopanofi.pdf
    • http://bbu.vn/Images_upload/files/nunafuz.pdf
    • http://geology.ie/wp-content/plugins/formcraft/file-upload/server/content/files/16073d8485d0d9---fawomakifawuxutemukuxob.pdf
    • https://eccdc.org/application/webroot/userfiles/file/70955284352.pdf
    • https://www.tessilgiada.it/wp-content/plugins/formcraft/file-upload/server/content/files/160a926e0c7815---mudite.pdf
    • https://arenda1s.ru/wp-content/plugins/super-forms/uploads/php/files/befe97aa47a485cea464c67c90760c3e/xigudedagagizusizemavuw.pdf
    • http://kwik-it.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16099bba6a4dbb---80971775421.pdf
    • http://www.blackhillsdancecentre.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d8999991f6---nifefani.pdf
    • http://www.sunarpazarlama.com/wp-content/plugins/super-forms/uploads/php/files/idj1275bi7gmridp1bsk0llf77/81492445588.pdf
    • https://www.vbclighting.com/wp-content/plugins/super-forms/uploads/php/files/eccd1a7768c1b259e85dccee16cc22db/42987671990.pdf
    • http://septumdent.com/img/userfiles/files/60558700027.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=reflection+across+y+axis+equation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e826.bin
3911eedd00820ffc19437b4263d9a7f8e47377371bc1bb84f03c0957f717fe16
pdf-font-stream PDF embedded font (sfnt) at offset 0xE826 18488 bytes
font_01_sfnt_off0001192e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1192E 16792 bytes
font_02_sfnt_off00013145.bin
2070b1da6ee2673f073549e0942a0fa3e9860e99b767cb197dd4f81d10f6448a
pdf-font-stream PDF embedded font (sfnt) at offset 0x13145 10836 bytes