Malicious PDF — malware analysis report

Static analysis result for SHA-256 615d8fbe32ca1446…

MALICIOUS

PDF

102.9 KB Created: 2021-08-30 01:55:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 7a9c4298fade0c7a1e3ab30975e35428 SHA-1: dd0debe928bec6e1081384054bd708ad5f188056 SHA-256: 615d8fbe32ca14465ad31ee03976006ae36e3ed466735857a727b0dcc941f465
156 Risk Score

Malware Insights

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

The PDF was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm hosted on compromised CMS upload storage, with many distinct hosts and disposable domains, suggesting an attempt to distribute malicious content or phish users. The embedded URLs point to various PDF files on these compromised sites, likely serving as a lure or a redirector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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://htfcompact.com/wp-content/plugins/super-forms/uploads/php/files/8b78ecbd52afb0fe9f8202798dc6407d/30052526018.pdf In PDF document text
    • https://gamletaarnhuset.no/wp-content/plugins/formcraft/file-upload/server/content/files/1607bf5ca1c388---xenenuv.pdfIn PDF document text
    • https://www.financedeclined.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1606cbfbbe0c1f---valegobipamenokovukidezad.pdfIn PDF document text
    • http://akbmodel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608218a54d0fc---dizarotixazejimixeno.pdfIn PDF document text
    • http://aristosaigonhotel.vn/uploads/files/lejafejigutowelibikumumeg.pdfIn PDF document text
    • https://olgunbey.com/upload/ckfinder/files/52038198644.pdfIn PDF document text
    • http://zonwering-nederland.eu/ckfinder/userfiles/files/61789983371.pdfIn PDF document text
    • http://kahasat.cz/data/file/26851018036.pdfIn PDF document text
    • https://kede.org/userfiles/file/mixamefa.pdfIn PDF document text
    • https://kfz-gutachter-oliver-schiller.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608299d062d07---vaxujol.pdfIn PDF document text
    • http://azizolace.cz/images/file/kagobusolofenimebugu.pdfIn PDF document text
    • https://thic.net/plugin/ce1/ckfinder/userfiles/files/gukuje.pdfIn PDF document text
    • http://vonschickenconcord.com/uploads/files/8843071076.pdfIn PDF document text
    • http://ondrejkocar.cz/img/file/xidikazurafakerebi.pdfIn PDF document text
    • http://bagandpack.ru/wp-content/plugins/super-forms/uploads/php/files/a589eb538ebc30d37acb48f376e2e920/vujowitulowixubim.pdfIn PDF document text
    • https://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/16084381c203a6---rimonefesifamebunap.pdfIn PDF document text
    • https://www.partyshuttlebus.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160bfd9d117fa2---42341639222.pdfIn PDF document text
    • https://108pizza.pl/uploads/userfiles/files/jupijiziredutixar.pdfIn PDF document text
    • http://www.hotel-margherita.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bb292adee62---58326200751.pdfIn PDF document text
    • http://kovacsoltvaskerites.hu/images/file/dipisiroja.pdfIn PDF document text
    • http://lawyerstitleescrow.com/clients/9/9b/9b7cfcecb5e5abb6b877b2b1d59b4eb1/File/sinofi.pdfIn PDF document text
    • http://tinavaron.com/ckfinder/userfiles/files/44314373509.pdfIn PDF document text
    • https://rescue.bg/wp-content/plugins/formcraft/file-upload/server/content/files/160cff67574dec---74080454296.pdfIn PDF document text
    • https://xlspandoek.nl/userfiles/file/23313213609.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=chemistry+practice+test+1+answersPDF 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_off0001281c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1281C 10756 bytes
SHA-256: fc3c1ec8a685a4352e7728d11853dacc4e1eb5774e5095f5d6e9d47682e4d359
font_01_sfnt_off000140d3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x140D3 20188 bytes
SHA-256: 5a9644ad311c37d3d0bb8e907d82bd37659cb5c0f5614649b8556361c297d20a
font_02_sfnt_off000174f8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x174F8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1