Malicious PDF — malware analysis report

Static analysis result for SHA-256 39854c27c4d9b275…

MALICIOUS

PDF

78.3 KB Created: 2021-07-03 00:29:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 9cb73014a9f38cb59eb75e621efb83ff SHA-1: 7d7bfd0637bf0a0138f54fcab1a51260fab3e9f6 SHA-256: 39854c27c4d9b275e990d1ef8f41c3b76498e68de66152c3ab2088adf9449253
156 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, indicating it likely contains exploit code. It functions as a link farm, with numerous embedded URLs pointing to compromised CMS uploads and disposable domains. These links are designed to lure users to potentially malicious sites, consistent with phishing or malware delivery campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://wych123.com/upload/files/91972733165.pdf
    • https://advancedbusiness.co/wp-content/plugins/super-forms/uploads/php/files/c730bdafa99a9bbb7ff7d48e01cb1216/83151835666.pdf
    • https://www.ogblfrontaliers.fr/wp-content/plugins/super-forms/uploads/php/files/2t3qa29nrnd5c6o1ujkppr6et1/sutikoxevomidupex.pdf
    • http://churchliferesources.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a292c93236a---nebibufilifaxulivoxofi.pdf
    • https://proff-doors.ru/wp-content/plugins/super-forms/uploads/php/files/de566c7896e02407cab44c713c5c2c89/bilozivadunomisezib.pdf
    • http://www.greenbriarpropmgmt.com/wp-content/plugins/super-forms/uploads/php/files/66ac7593b310b8a57a67e4a0697e3e02/28248556338.pdf
    • http://www.hkwebdesign.com.hk/wp-content/plugins/formcraft/file-upload/server/content/files/1607dd1d517c5c---wiwuxudafajib.pdf
    • http://cs-golfclub.com/ckupload/files/2561272748.pdf
    • https://emauto.lv/index/images/up/file/11344358903.pdf
    • http://artmetinc.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087e1be7526e---4775704403.pdf
    • http://www.suffaheducation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b9cda42b001---pukode.pdf
    • http://www.ddd-iasi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16094ba73c1625---342940970.pdf
    • https://www.medicalart.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16094d06059627---fumej.pdf
    • http://tafgambiatours.com/userfiles/file/64038909014.pdf
    • https://www.reliancecareuk.com/wp-content/plugins/super-forms/uploads/php/files/1e9a2b0eeb50e5e7a9d3b8d82a0beae0/66705999714.pdf
    • http://sarlampa.ru/upload_picture/ratunakufufedata.pdf
    • https://coloreverything.love/wp-content/plugins/super-forms/uploads/php/files/deb44e4c8ddbc88dc26b0dd470c4d3c7/luvixik.pdf
    • https://alignerco.com/wp-content/plugins/super-forms/uploads/php/files/30fcbbb86a2f45edba45b9ae69a785af/novuzosugidepijuxoro.pdf
    • https://sharidendesignasphalt.com/wp-content/plugins/super-forms/uploads/php/files/915b1b5924b9ed2e2fdd50506c1eaaf2/sujulupuvotalakavutitux.pdf
    • http://rajskiewakacje.pl/userfiles/file/7180797965.pdf
    • http://nova-auto.com/upload/47627278217.pdf
    • http://bizwd.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c116442fcbc---ramujumomitirekupil.pdf
    • https://www.tangelo.no/wp-content/plugins/formcraft/file-upload/server/content/files/1607c5bd83d228---68802315859.pdf
    • http://whuntex.ru/userfiles/file/40085141721.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=business+article+review+example
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ce4f.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xCE4F 16792 bytes
font_01_sfnt_off0000e666.bin
59ce8f1df0698d6ea06646673250ae2e21d3370fbd0285b53241dfc791d5ad20
pdf-font-stream PDF embedded font (sfnt) at offset 0xE666 10824 bytes
font_02_sfnt_off0000ff77.bin
05431576e3a95dd5f2b365d89dc4d20be0a8e6feb386c80e80fbbd71cff0681b
pdf-font-stream PDF embedded font (sfnt) at offset 0xFF77 16984 bytes