Malicious PDF — malware analysis report

Static analysis result for SHA-256 4235ccfcfab7755b…

MALICIOUS

PDF

88.5 KB Created: 2021-07-22 22:29:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: ec6452a0147738f9794049e6666b283b SHA-1: 76dcd702168b876c76ae4d7f21a5820f4c039a99 SHA-256: 4235ccfcfab7755bbc1f7a804a92e00ba68fd802576d59aa94eb25780b47b681
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to compromised CMS uploads and disposable hosting domains, a common tactic for phishing or distributing further malware. The ML classifier and ClamAV detection strongly indicate malicious intent. The file's structure and link farm nature suggest it's designed to lure users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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 http://skipjackpoke.com/ckfinder/userfiles/files/36216572064.pdf In PDF document text
    • http://industrialdevices.in/uploads/lenefojujudokuma.pdfIn PDF document text
    • https://www.babetravelling.com/ckfinder/userfiles2/files/vutix.pdfIn PDF document text
    • http://alnoorcity.com/userfiles/file/vipoteguxifaxal.pdfIn PDF document text
    • http://krzysztofmalec.pl/gfx/fck/file/misipanewarosuxebijiv.pdfIn PDF document text
    • https://amartzon.store/wp-content/plugins/super-forms/uploads/php/files/8c75498174cd8314f7e3d76435e8d199/61091723516.pdfIn PDF document text
    • http://akicgiyim.com/userfiles/file/jeduzaj.pdfIn PDF document text
    • https://unosms.us/userfiles/file/30420510095.pdfIn PDF document text
    • http://woonhuislift.info/wp-content/plugins/formcraft/file-upload/server/content/files/160b22d48390a6---41628333767.pdfIn PDF document text
    • http://creative-format.com/upload/editor/files/balikuvukuk.pdfIn PDF document text
    • http://www.sg-callenberg.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b7d22f47a31---pasaretowurozagosuzezuti.pdfIn PDF document text
    • https://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/4454d0783949d7771b769340ab45798d/zatobibexa.pdfIn PDF document text
    • http://aiswaryamatrimonials.com/fck_uploads/file/83792115027.pdfIn PDF document text
    • http://accessprecision.com/userfiles/file/bujibumeguxixuwitosojej.pdfIn PDF document text
    • http://uro-medical.pl/zdjecia/fotki/file/punobev.pdfIn PDF document text
    • http://thsport.dk/ckfinder/userfiles/files/94033647800.pdfIn PDF document text
    • http://www.psstrecno.sk/wp-content/plugins/formcraft/file-upload/server/content/files/1606d687d859a7---9379941566.pdfIn PDF document text
    • https://swotin.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b93395caf04---54376435609.pdfIn PDF document text
    • https://pnp-studio.com/fckeditorfiles/file/zuwep.pdfIn PDF document text
    • https://bettenbaehren.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a492b4b04c5---jotirapelumaripofujuxom.pdfIn PDF document text
    • http://sistersaviopublicschool.com/userfiles/file/putinizusexeramon.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=itp+platelet+countPDF 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_off0000f6e8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6E8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010eff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10EFF 10060 bytes
SHA-256: 1773a6ea5cb96a9d5bb34360dd7d033d23bf83437484255402ec24fb4b421a77
font_02_sfnt_off00012584.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12584 17892 bytes
SHA-256: ebf1241febceabc2e791b1c374db321e85549528a7ec9e9c291a07188a2c7441