Malicious PDF — malware analysis report

Static analysis result for SHA-256 57351ce5848076de…

MALICIOUS

PDF

125.5 KB Created: 2021-09-17 07:28:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 9831bad957fd9e28c2d991cfdf55a1b6 SHA-1: 1ac45ea627fc43e48de5aafb4dbf2e8979fab04f SHA-256: 57351ce5848076dec6e35db8f7fca1b13f66176e7acd4df52b0a671f25b35014
104 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is often used to redirect users to malicious websites or exploit vulnerabilities. The document also features a large number of external URIs, many hosted on compromised CMS platforms, suggesting a link farm or phishing attempt. The ML classifier strongly indicates malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

Heuristics 6

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://pixomot.ru/uplcv?utm_term=the+100+book+by+michael+hart+pdf PDF link annotation
    • http://cageart.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16141d2ad0e16e---gatebofidipazikiguxanazus.pdfIn PDF document text
    • https://rhythmcprandfirstaid.com/wp-content/plugins/super-forms/uploads/php/files/444302a83f742cbd8e7bf4158c7a4dec/lenogajeripanuwof.pdfIn PDF document text
    • https://mongolia-volkslift.com/uploads/files/wewuk.pdfIn PDF document text
    • http://letnipohar.cz/upload/file/kelutasefozasiguzupab.pdfIn PDF document text
    • http://dieutrimun.myphamkangnam.vn/webroot/img/files/59132238364.pdfIn PDF document text
    • http://www.virtualaid.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1613ffc1e547ed---22828471742.pdfIn PDF document text
    • https://www.iieng.org/editor/ckfinder/userfiles/files/zodejusafinofuko.pdfIn PDF document text
    • https://gemicilojistik.com/userfiles/upload/file/bijowarumok.pdfIn PDF document text
    • http://tentauto23.ru/ckfinder/userfiles/files/govebu.pdfIn PDF document text
    • http://urbanposthotel.com/admin/ckfinder/userfiles/files/43272036344.pdfIn PDF document text
    • https://turkeyinsurance.info/images/file/sugiturok.pdfIn PDF document text
    • http://teakdeck.pl/files/file/dagusisiboworonizozezowep.pdfIn PDF document text
    • https://kvizek.hu/ckfinder/userfiles/files/lajaxodoweritemija.pdfIn PDF document text
    • http://xn--90afqerdlt1f.xn--p1ai/admin/ckfinder/userfiles/files/tugolazujoxuberovivak.pdfIn PDF document text
    • https://arnetbilgisayar.com/upload/ckfinder/files/58277519142.pdfIn PDF document text
    • https://www.kindspring.org/inc/ckfinder/userfiles/files/63580447171.pdfIn PDF document text
    • http://www.valaisconsulting.ch/file/gigesafev.pdfIn PDF document text
    • http://ikuma-car.com/js/upload/files/katovijaj.pdfIn PDF document text
    • http://yatros.ro/wp-content/plugins/formcraft/file-upload/server/content/files/161324488b493a---76134951018.pdfIn PDF document text
    • http://uniroll.pl/user_images/file/soriselez.pdfIn PDF document text
    • https://dalycity.com/wysiwygfiles/file/sorujuda.pdfIn PDF document text
    • https://sledovani2.gpshlidac.cz/www/userfiles/files/xanazotobojulolelomix.pdfIn PDF document text
    • https://ivfnna.gr/wp-content/plugins/super-forms/uploads/php/files/cd85e9a70045f22b3014f58b2db2cb3f/19317978776.pdfIn PDF document text
    • 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_off00018341.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x18341 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00019b58.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x19B58 11096 bytes
SHA-256: 42d221955837980ee40a4b2b1b2859fcf3637741d5631e63ce661184e50154e6
font_02_sfnt_off0001b50c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1B50C 19404 bytes
SHA-256: 925d0ba7160468ee83aa3ea6eba55f1df33b2418a1c9a062aaa845be476ee2dd