Malicious PDF — malware analysis report

Static analysis result for SHA-256 9f9a01de410c0f83…

MALICIOUS

PDF

80.4 KB Created: 2021-09-07 01:16:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 742a1c2fc650c21d553719b61da2540c SHA-1: bc9cc20b920c71a4fbdd15a88020b04e2c9a02a4 SHA-256: 9f9a01de410c0f83b2bbec9d654504d5a1b39f1c43b213950e21581e7190174e
104 Risk Score

Malware Insights

The PDF contains an embedded JavaScript stream and numerous external URIs, many of which point to compromised CMS upload directories. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of using disposable hosting for a large number of links, suggesting a link farm for SEO manipulation or to distribute malicious content. The ML classifier also strongly flagged this PDF as malicious.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://chcial.ru/uplcv?utm_term=introduction+to+psychology+by+baron+pdf+free+download PDF link annotation
    • http://herculesestateplanning.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/mirosutakuzodulozabeva.pdfIn PDF document text
    • http://www.kidnuri.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135f0d5b59f9---genusimaretov.pdfIn PDF document text
    • https://danielstrehlau.com/userfiles/file/18461063382.pdfIn PDF document text
    • http://www.mustwalge.ee/data/content/files/62711911887.pdfIn PDF document text
    • https://www.sixteengrams.com/wp-content/plugins/super-forms/uploads/php/files/1mlt4a7hpp890k0jo80495ou1q/9101647499.pdfIn PDF document text
    • https://pabausa.org/wp-content/plugins/formcraft/file-upload/server/content/files/160f3968147779---33231012031.pdfIn PDF document text
    • http://www.next-conseil.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16079e113662ca---fuguvonatopuxexeg.pdfIn PDF document text
    • http://www.ih-consultant.com/ckfinder/userfiles/files/kotewarusedemuxob.pdfIn PDF document text
    • http://www.adanakursmerkezi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a755715810d---fikilevubuk.pdfIn PDF document text
    • https://www.napariverinn.com/wp-content/plugins/super-forms/uploads/php/files/5cc70c557cb403473f97aa2409c56619/popodaxetem.pdfIn PDF document text
    • http://salman-is.com/userfiles/file/78365363178.pdfIn PDF document text
    • http://goteneplast.se/files/images/file/puvikufidibir.pdfIn PDF document text
    • http://printrun.nl/userfiles/files/lekekezav.pdfIn PDF document text
    • https://adikkeempat.com/contents/files/witotirajajipazamakogezu.pdfIn PDF document text
    • https://flycam.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16089b463ea165---rixazoxibapoji.pdfIn PDF document text
    • http://i-physiology.ru/upload/bakesezagogixaxifogevuja.pdfIn PDF document text
    • https://www.properties-thassos.com/wp-content/plugins/super-forms/uploads/php/files/fbngbn0qfvp437m931l95hlqam/gamefudawodisufitawomi.pdfIn PDF document text
    • http://hodori247.com/uploads/files/bupukukevobasimaxuk.pdfIn PDF document text
    • http://thegrcinstitute.org/app/webroot/js/ckfinder/userfiles/files/70690593919.pdfIn PDF document text
    • https://newtech-utm.pl/userfiles/file/87445210990.pdfIn PDF document text
    • https://www.lamuccacompany.com/wp-content/plugins/super-forms/uploads/php/files/f0371eee0ef51282718e403b932b33fd/33000666212.pdfIn PDF document text
    • https://kuechentreff-schmid.de/wp-content/plugins/super-forms/uploads/php/files/44o9avmmm6lunm9oesttcc9eqg/tepajeweripuvepejukuba.pdfIn PDF document text
    • http://portalinmobiliario24.com/uploades/fckeditorfile/66789755807.pdfIn PDF document text
    • https://fortlauderdale-carservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609d4d9b18f73---pazumisidupuzosomuge.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_off0000d0c4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD0C4 18944 bytes
SHA-256: b2d7e7df09e56d4246b49379c2cf76de5aafdf36801ca9392a88dd367a3ad1b1
font_01_sfnt_off00010236.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10236 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011a4d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A4D 11292 bytes
SHA-256: cebdacc98b59030ce94c523ce7e5c3b135cfbfffbd8bbafdf93429347aedc48f