Malicious PDF — malware analysis report

Static analysis result for SHA-256 e100c33c38e45a43…

MALICIOUS

PDF

95.4 KB Created: 2021-07-06 00:42:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: d6985f373e9c99401eaafe28e6defbd1 SHA-1: 3351972d31822d5dd693c49435aa28742ce24667 SHA-256: e100c33c38e45a43f498f3300c8db21c88e291aac407930e0d6703cab4aa7fad
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 WordPress sites, indicating a link farm designed to redirect users to malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware distribution. No scripts were extracted, and the document body was unreadable, so the analysis relies on the PDF structure and embedded URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9929

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://rethabise.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160742b2a76df3---vubebisikawufinuw.pdf In PDF document text
    • https://www.hed-endo.hr/wp-content/plugins/formcraft/file-upload/server/content/files/1606fa0e67c073---nuxifi.pdfIn PDF document text
    • https://www.sadcmedia.com/wp-content/plugins/super-forms/uploads/php/files/s1dhnt33uo5b193jucpr2cdblt/92082134332.pdfIn PDF document text
    • http://aitrans.org/UploadFile/file/F1202105140958107409.pdfIn PDF document text
    • https://xlux.vn/wp-content/plugins/super-forms/uploads/php/files/gj64i8quqdtiq0tn3ev0pt6usq/wetexoronalujoredagawefer.pdfIn PDF document text
    • https://www.helpfulhunks.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160c65af39276e---tisadifugejakaloxebeg.pdfIn PDF document text
    • https://www.ideaklinikbursa.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082e010ca63e---15637600698.pdfIn PDF document text
    • http://meandnetworking.com/ckfinder/userfiles/files/fagadatila.pdfIn PDF document text
    • http://ideviceplus.nl/app/webroot/files/userfiles/files/nebezidit.pdfIn PDF document text
    • http://citygclub.com/ckupload/files/minon.pdfIn PDF document text
    • http://www.predia.cz/userfiles/file/83332564180.pdfIn PDF document text
    • https://www.espymetcalf.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a9aeb1b55a5---44056196165.pdfIn PDF document text
    • http://szyldkj.com/luodan/images/userfiles/file/jisuzijewamigefugul.pdfIn PDF document text
    • http://www.patricktennis.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1609d1f0aebe0a---bisefubemomaborajidugudef.pdfIn PDF document text
    • https://red-adlay.com/upload/files/fejaworov.pdfIn PDF document text
    • http://thietbixanh.net/uploads/files/kozozu.pdfIn PDF document text
    • https://arrayamed.com/userfiles/file/fumanajusuwulogisogo.pdfIn PDF document text
    • https://africanresearchcenter.com/userfiles/file/pugogul.pdfIn PDF document text
    • http://hrjok.com/uploadfile/file/putepolujime.pdfIn PDF document text
    • http://automotiveenergy.cz/userfiles/file/kiramijefebajaxosegudub.pdfIn PDF document text
    • http://vietthanhstone.com/images/news/file/joruji.pdfIn PDF document text
    • https://janeunchained.com/wp-content/plugins/super-forms/uploads/php/files/kpm3gaolsql3srvgv1depai3a9/18052697807.pdfIn PDF document text
    • http://bawaconstructions.com/editorData/file/94498825675.pdfIn PDF document text
    • https://dermo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076c9f89e81c---99472476723.pdfIn PDF document text
    • http://xn--90ad5ackt1d.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/9f4e75f1d35b3e4618e11a60f4a52de9/5672554277.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=blank+doctors+note+template+pdfPDF 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_off0001118f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1118F 10832 bytes
SHA-256: bb4645a6466da8302f29ba26fdd2cf313431235d05304cb937a27b317bb86545
font_01_sfnt_off00012a92.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12A92 17036 bytes
SHA-256: 7aba351102687e7dce1db9d28597962a6f5a40579ca0ccebe4b28c9a7f4436fa
font_02_sfnt_off000156a4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x156A4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1