Malicious PDF — malware analysis report

Static analysis result for SHA-256 ef1b453126367a39…

MALICIOUS

PDF

83.0 KB Created: 2021-09-03 20:44:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: d3e770a1525d0c9e9360bf613cfbc034 SHA-1: 62f847bafc3206cea823fc924a5e078f937d31ed SHA-256: ef1b453126367a39d8553ee9d11c9ae5ac029f9c7b598873663c68d2c11a9d88
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external resources, many of which point to compromised CMS uploads or disposable hosting, suggesting a phishing or malware distribution lure. The ClamAV detection and ML classifier strongly indicate malicious intent. While no scripts were explicitly extracted, the nature of the links and the PDF structure suggest it's designed to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 7

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://floraplant.gr/FCKeditor/userimages/file/70299997898.pdf In PDF document text
    • http://www.agrosystem.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1608a43323207a---fagatamigesabuxi.pdfIn PDF document text
    • http://alnadaoil.com/userfiles/file/24015045917.pdfIn PDF document text
    • http://profesniprukaz.cz/ckfinder/userfiles/files/55281822540.pdfIn PDF document text
    • https://orkhaconstruction.com/wp-content/plugins/super-forms/uploads/php/files/el64gfahc7nu7b2059pr5s0f9f/32243570602.pdfIn PDF document text
    • https://balbok.net/admin/ckfinder/userfiles/files/nopugakojeriwoxup.pdfIn PDF document text
    • http://dailyxedayhang.com/userfiles/files/desojomixowagikogar.pdfIn PDF document text
    • https://schreinerheusi.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609910b4ba809---90618488696.pdfIn PDF document text
    • http://totaleclipsenv.com/wp-content/plugins/formcraft/file-upload/server/content/files/16074a448e0ddb---94175607404.pdfIn PDF document text
    • https://regeneracion-capilar.com/wp-content/plugins/super-forms/uploads/php/files/666e0a0f049d6bfdfe8e59859d327308/wuderubemikati.pdfIn PDF document text
    • https://dmvassociates.com/wp-content/plugins/super-forms/uploads/php/files/a921d0966825e7a34fa720b645544c58/vewodozefosupor.pdfIn PDF document text
    • https://komunalno-vrgorac.hr/files/26454022253.pdfIn PDF document text
    • http://graphicon.hu/wp-content/plugins/formcraft/file-upload/server/content/files/1606f6331195f7---71940857966.pdfIn PDF document text
    • http://gaziogluenerji.com/images_upload/files/1148436938.pdfIn PDF document text
    • https://juhaszautovill.hu/userfiles/file/zoxalo.pdfIn PDF document text
    • http://www.contal-farmer.com/uploads/files/fomoleguzabenekigejavuj.pdfIn PDF document text
    • https://www.bountyvacation.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e1e157b75b---dojaju.pdfIn PDF document text
    • https://dacoma.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16089c22bd877f---31778640640.pdfIn PDF document text
    • https://www.mobytec.com.br/mobytec/wp-content/plugins/formcraft/file-upload/server/content/files/160bbbd4c46a8c---jerukonewolaposam.pdfIn PDF document text
    • http://metapolar.hu/tmp/79777951283.pdfIn PDF document text
    • http://www.thaiboat.net/image/upload/File/76428793765.pdfIn PDF document text
    • https://ltssinternational.com/res/wysiwyg/file/wurefijijufoxamafaf.pdfIn PDF document text
    • http://ambulatorioveterinarioilghirlandaio.it/userfiles/files/62140970309.pdfIn PDF document text
    • https://bikinibody.be/wp-content/plugins/super-forms/uploads/php/files/q183ocne2oror6ng317p8p4njl/naxufafewiris.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=searchable+pdf+bluebeamPDF 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_off0000df31.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF31 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f743.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF743 18168 bytes
SHA-256: 1b8c1b5b9bea9690529a243c6fe479d4b5d01ed2cebd4f1b798b28d53361e317
font_02_sfnt_off000125ee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x125EE 10616 bytes
SHA-256: def9a47183e56af27bd95e26ffa625156857092ec1556be7464c48d6357c047c