Malicious PDF — malware analysis report

Static analysis result for SHA-256 37fec992d2704834…

MALICIOUS

PDF

85.2 KB Created: 2021-09-11 22:22:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 8b89b7e0f69850092902f72fc60cc1e4 SHA-1: ca5d10f3fa2281fb22e051f2dc89fa4c615d497d SHA-256: 37fec992d27048342fb738996227ba3339d61302a2f50a55d860577232152359
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, many of which point to PDF files hosted on various domains, suggesting a link farm or redirection mechanism. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating a pattern of using disposable hosting for numerous links. While no scripts were explicitly extracted, the nature of the embedded URLs and the overall detection suggests the PDF is likely used to redirect users to malicious sites, potentially for phishing or to download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9930

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 http://phukiendoxe.com/media/ftp/file/tezuminutafuguko.pdf In PDF document text
    • http://dalnoboy.net/data/filestorage/upload/files/mivudixesumozebuxilug.pdfIn PDF document text
    • http://tichdiem.surecare.vn/uploads/userfiles/file/46186340141.pdfIn PDF document text
    • https://merohamro.com/ckfinder/userfiles/files/potudupa.pdfIn PDF document text
    • http://dblbtech.com/userfiles/file/wabulomadiruzobijese.pdfIn PDF document text
    • https://institut-arabe.org/ckfinder/userfiles/files/sadorurubivexajepodabaf.pdfIn PDF document text
    • https://tomaszbizon.tomaszbizon.pl/web/uploads/files/bejugonegeved.pdfIn PDF document text
    • http://snnet.kr/board_pds/fckeditor/2021/09/file/46450659899.pdfIn PDF document text
    • https://www.reparaciondebomba.com.ar/wp-content/plugins/super-forms/uploads/php/files/iioffbbqtngv12qg5ttfqo89v2/vevazamukavuvew.pdfIn PDF document text
    • http://belstroyiz.ru/img/file/98857035887.pdfIn PDF document text
    • http://barudan.hk/UploadFile/file/20210905025446055.pdfIn PDF document text
    • http://hwayoung.kr/upfile/files/giduxirifiv.pdfIn PDF document text
    • http://e-sheremet.com/img/sajoxesefejifalakavaso.pdfIn PDF document text
    • http://co-mit.com/uploads/files/53077642230.pdfIn PDF document text
    • http://mueblesdepladur.es/1/userfiles/file/89739280350.pdfIn PDF document text
    • http://soleilboo.com/images/uploads/files/gomikofalafibak.pdfIn PDF document text
    • https://metroguards.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161356a66996c4---54936495591.pdfIn PDF document text
    • https://machinex-machines.com/UserFiles/File/23943792158.pdfIn PDF document text
    • http://okfilm.kr/userData/board/file/52826967508.pdfIn PDF document text
    • https://www.whoamiandwhyamihere.com/ckfinder/userfiles/files/juvepefagapuvit.pdfIn PDF document text
    • https://www.wizzfizz.com.au/application/third_party/ckfinder/userfiles/files/wajorebek.pdfIn PDF document text
    • http://studioassociatoemc.com/userfiles/files/kagulapuvofejinisalarev.pdfIn PDF document text
    • https://www.phuketvillarentalandservices.com/ckfinder/userfiles/files/daxuge.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=miracast+apk+for+tvPDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c94a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC94A 16380 bytes
SHA-256: e20f1319638ac6d62e038bfb61794e41c6722a1afaf37180ebac22a32562fdb7
font_01_sfnt_off0000dfde.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFDE 22272 bytes
SHA-256: 2583ca780935353d1fd9809d87dccda09c781957bde830bbcd1a215aa8ada4c4
font_02_sfnt_off00011777.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11777 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_03_sfnt_off00012f8e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12F8E 10344 bytes
SHA-256: a78a862d36ac4c9fbc87eb8fde1ea1ebafed7cf317e3d9e2d739ad36e6bd6ac7