Malicious PDF — malware analysis report

Static analysis result for SHA-256 2d91368bbd07eee2…

MALICIOUS

PDF

74.6 KB Created: 2021-09-12 11:15:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: fb0da30d178ba7028fb0f7e95198643c SHA-1: 8051ff3fdd5c033f24eb791d81afc9055989d53b SHA-256: 2d91368bbd07eee213bf4fbfac4b88a858cf035accd55b054f22b8a93dfaa965
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised CMS uploads and disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery. No scripts were extracted, but the structure and URL analysis are sufficient to infer the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://brusroom.com/wp-content/plugins/super-forms/uploads/php/files/e8f988164b97fff72c135c9350a6ec25/gijoxi.pdf In PDF document text
    • http://hani-bee.com/userfiles/files/40361368452.pdfIn PDF document text
    • http://noithatlekhanh.com/Images_upload/files/10702153317.pdfIn PDF document text
    • https://cet.sk/res/file/sumame.pdfIn PDF document text
    • http://kbautotech.com/board/datafiles/imagefile/sapuvigeziberotixivi.pdfIn PDF document text
    • https://esz.jp/img/editor/files/83890928909.pdfIn PDF document text
    • http://www.eurosecurimed.com/ckfinder/userfiles/files/vimilesewul.pdfIn PDF document text
    • https://srilangkapools.com/contents/files/wupoxotuzixabevofab.pdfIn PDF document text
    • https://wendi101.com/userfiles/file/sixizagenomalesifominuzo.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137e16942ef7---32190173960.pdfIn PDF document text
    • http://nemeckystrakac.sk/editor_uploads/files/komumiruwodumasosuloxumi.pdfIn PDF document text
    • https://sistemagestiondpr.com/userfiles/file/93563022271.pdfIn PDF document text
    • http://vodova51-53.cz/files/25787742398.pdfIn PDF document text
    • http://www.niziointerior.pl/upload/file/57024053180.pdfIn PDF document text
    • http://chemonova.com/FCKeditor/file/tekowov.pdfIn PDF document text
    • http://betonkeritesek.eu/Content/files/disekisuzolak.pdfIn PDF document text
    • http://goksirkrupskimlyn.pl/img/upload/files/13701235924.pdfIn PDF document text
    • http://dsacare.com/admin/uploads/file/98562155194.pdfIn PDF document text
    • https://manhremhoangvan.com/wp-content/uploads/files/medulupuxaditidu.pdfIn PDF document text
    • https://bosgo.mn/uploads/files/jolizimagegu.pdfIn PDF document text
    • http://palami.by/images/file/fetatisifosurobevuwataf.pdfIn PDF document text
    • http://magooferta.pl/uploads/fck/file/viwaj.pdfIn PDF document text
    • http://yeditepegumruk.com/userfiles/20955278745.pdfIn PDF document text
    • http://vasilii-orlov.fun/wp-content/plugins/super-forms/uploads/php/files/e858a2b9db7bd0fd88e0b4765fb1c88d/mebigitalivitesevepigeg.pdfIn PDF document text
    • https://www.playitdirect.ca/ckfinder/uploadfiles/files/37659193372.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=best+website+to+watch+boxing+freePDF 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_off0000be73.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBE73 17188 bytes
SHA-256: 7f4014402c11c52ba4c9dbb267b716c81986fe620b068decae192bb6bfc27174
font_01_sfnt_off0000eacf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEACF 10952 bytes
SHA-256: d776b9c90090dd315caadb959175eebcf7b275dfeeea3a4ec88002dd5b883dfc
font_02_sfnt_off00010455.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10455 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1