Malicious PDF — malware analysis report

Static analysis result for SHA-256 d65b4924ddf4e105…

MALICIOUS

PDF

89.8 KB Created: 2021-06-29 14:59:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 07945b3c81085eb1bffb4932e0538e95 SHA-1: 322d0cf3805a3fc46a399e9db5feb0a3e78b1767 SHA-256: d65b4924ddf4e105d848d2e99b5d838c8e5f247981632aacf208dd6d1716e3cb
96 Risk Score

Malware Insights

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

The PDF document contains a large number of embedded URLs, many of which point to compromised WordPress upload directories or disposable hosting. This suggests the document is designed as a link farm to distribute further malicious content or facilitate phishing attacks. The ML classifier strongly indicated maliciousness, supporting this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://asiquim.com/ckfinder/userfiles/files/76021473913.pdf
    • https://gulertrafik.com/wp-content/plugins/super-forms/uploads/php/files/f1gs6ndma010bogj5u3c61mifd/lebakepi.pdf
    • http://s8radziejowice-paszkow.pl/userfiles/file/modesitevuvopejusajig.pdf
    • https://protechlighting.com/wp-content/plugins/super-forms/uploads/php/files/790a4dcdd24d7aa98017b3bf1865e357/58388001367.pdf
    • https://szud94.hu/img/sajatfile/files/bepawirazexu.pdf
    • https://festival.bg/fckeditorfiles/file/66296895603.pdf
    • https://www.pennlighting.com/wp-content/plugins/super-forms/uploads/php/files/c93d5aab36a9eb9d5db42fad05abf5e2/75233699927.pdf
    • http://dgjst.com/upfile/file/97816094803.pdf
    • https://microfocus-realize2020mea.com/wp-content/plugins/super-forms/uploads/php/files/9e5a60d96319e3bf047f2d2b318d485c/50344970920.pdf
    • https://asharfilalkulfi.com/ckfinder/userfiles/files/56240708401.pdf
    • http://www.alexgis.com/siteuploads/editorimg/file/86679560025.pdf
    • https://ontime-taxi.kg/wp-content/plugins/super-forms/uploads/php/files/966170bc3831289d1ab8243928ced5b8/naxugaduwegugiwimu.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160834c72c7c00---fepumerakuzujibutopete.pdf
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1609e3e5e624ab---poxujidoxarazegonuxenuged.pdf
    • https://polinagerz.ru/wp-content/plugins/super-forms/uploads/php/files/chkcirkubachedbq8sfcrspoqv/31390814578.pdf
    • http://www.veronicaneal.com/wp-content/plugins/formcraft/file-upload/server/content/files/1/1606cbb17dcaff---jipox.pdf
    • http://anhbanglaw.com/userfiles/file/lozovixusugalimesifu.pdf
    • https://siyata.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/1607beae7366f8---43758235033.pdf
    • https://www.davinci.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1609296c0c7c66---kejutotujefotejodegifesuw.pdf
    • https://gionggiacam.com/ckfinder/userfiles/files/74825808594.pdf
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/bikp2839eiicrp6j70e16mtf0k/29626000935.pdf
    • https://transcendenceit.com/wp-content/plugins/super-forms/uploads/php/files/78cb9570e6c7262f131849000ed4b37f/dulanigo.pdf
    • https://clumba-indoor.ru/files/files/febinosakosi.pdf
    • http://sbstroy53.ru/img/files/bafexakimanigev.pdf
    • http://gayaarchi.com/userfiles/file/20210524220056.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=apple+crumble+with+coconut
    • 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_off0000f55e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF55E 16792 bytes
font_01_sfnt_off00010d75.bin
c6b4d40504eddd58a748daa69bfb51dd1715922e53237ceeddf8b7af285220cf
pdf-font-stream PDF embedded font (sfnt) at offset 0x10D75 10616 bytes
font_02_sfnt_off0001255b.bin
cedda8d6a2da8118f6354840b6bca51f021fd5347675c25ab81394a5b5998bf4
pdf-font-stream PDF embedded font (sfnt) at offset 0x1255B 19072 bytes