Malicious PDF — malware analysis report

Static analysis result for SHA-256 99f59b8d0e237727…

MALICIOUS

PDF

83.2 KB Created: 2021-09-21 21:49:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 36ca1de929391b70be489c529f1ae563 SHA-1: 0db59e059cf07f6226283d4b1e4bb1aabd37ae5a SHA-256: 99f59b8d0e2377270ed5d81de0f4e261083dfaac5f034f6fb17e2408764d1b9a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories or disposable hosting, indicating a link farm designed to obscure the final destination. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery. The presence of multiple compromised CMS upload links and link farms on disposable hosting are key indicators of this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://fitnessrev.net/wp-content/plugins/super-forms/uploads/php/files/5f85qvqnk6ppsftj047pebqbvl/wosekevizimipemesa.pdf In PDF document text
    • http://medical-1669.com/userfiles/files/gorezagikojoloxababisop.pdfIn PDF document text
    • http://sjhrz.com/images/upload/File/rejebafuxibaf.pdfIn PDF document text
    • http://www.gonouvellezelande.com/files/96300726309.pdfIn PDF document text
    • https://www.lipca.com/ckfinder/userfiles/files/dewiturotit.pdfIn PDF document text
    • http://thebankcardservice.com/uploads/files/2748228354.pdfIn PDF document text
    • https://propage.q-cloud.net/upload/ckeditor/pages/files/sewizogit.pdfIn PDF document text
    • https://novsport.com/content/File/nukonupazoli.pdfIn PDF document text
    • http://didaconcept.com/admin/fckeditor/file/lagade.pdfIn PDF document text
    • http://onlinetradeshow.ir/uploads/files/68250173288.pdfIn PDF document text
    • http://koyomisushi.com/uploads/files/fiwumagakositexemoda.pdfIn PDF document text
    • https://democv.associasuite.com/imagenes/contenidos/files/47996463310.pdfIn PDF document text
    • http://yourbuilding.ru/userfiles/files/guzigumufugewuxiruxarel.pdfIn PDF document text
    • http://musthighschool.mn/ckfinder/userfiles/files/9424594673.pdfIn PDF document text
    • https://afmiletisim.com/resimler/files/rejuponujo.pdfIn PDF document text
    • https://leavereview.com/customerinterview/ckfinder/userfiles/files/bifed.pdfIn PDF document text
    • http://smartmedicaleg.com/wp-content/plugins/formcraft/file-upload/server/content/files/161472dd6b6fc4---kiperobebud.pdfIn PDF document text
    • http://villaturri.com/wp-content/plugins/formcraft/file-upload/server/content/files/16147a62568cb4---nelotopemogesi.pdfIn PDF document text
    • https://univerosg.com/ckfinder/userfiles/files/75959427270.pdfIn PDF document text
    • http://turatabor.hu/media/4232775453.pdfIn PDF document text
    • https://greenways.at/userfiles/file/dulazazububagobogesimixu.pdfIn PDF document text
    • https://expobar.vn/app/webroot/files/images/pages/files/75454511435.pdfIn PDF document text
    • http://ksiclubcom.ksiclub.org/svnprojects/DHD/Source/images/files/gogogolosulaseven.pdfIn PDF document text
    • https://manorhair.com/uploads/files/202109050751171612.pdfIn PDF document text
    • http://philboyd.com/39389288932.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=get+chrome+dark+modePDF 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e1d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1D1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f9e3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9E3 17828 bytes
SHA-256: ee4567e8c0490ae65715e72369295ea0efd74fe4984f370f0e7deacc53a6021b
font_02_sfnt_off0001276e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1276E 10356 bytes
SHA-256: 8a95611d47e4b6fd231251f138335c9bc3be268452b3520a5ba803fe59c4bfd1