Malicious PDF — malware analysis report

Static analysis result for SHA-256 3a400bd2091d4e68…

MALICIOUS

PDF

95.2 KB Created: 2021-07-28 08:50:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 3eda58596456337ed079e25eef9869ef SHA-1: b6304f6b4b015a111f04aa7d8024ee0ca455fcd6 SHA-256: 3a400bd2091d4e680d3c363ee499684a891a452011bd1f6f5a266643f2ac8a5a
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, directing users to numerous PDF files hosted on compromised CMS uploads and disposable domains. This pattern is commonly used for phishing or distributing further malware stages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9984

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://vodnik48.ru/content/file/46270895709.pdf In PDF document text
    • http://nhatngungoisaoxanh.com/upload/files/42423284449.pdfIn PDF document text
    • http://coimbra.hu/uploads/ckfinder/userfiles/files/35501392859.pdfIn PDF document text
    • https://telewebmarketing.com/FCKeditor/file/72224371938.pdfIn PDF document text
    • http://buchtel1967.com/clients/26382/File/situtuveli.pdfIn PDF document text
    • http://heritagecarletonplace.com/clients/c/c2/c23aa4fb54f25340752d20cfcff880b2/File/14287691714.pdfIn PDF document text
    • http://bkm-market.net/userfiles/file/78830664577.pdfIn PDF document text
    • https://www.indee-r.fr/wp-content/plugins/super-forms/uploads/php/files/3e33b91c720b45d67399501e4ff85cf5/pogalu.pdfIn PDF document text
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/so72la04ovsom03c7hhihfj0k6/sixaxofegenumif.pdfIn PDF document text
    • https://drahmetbostanci.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b34d6c32f48---33330799650.pdfIn PDF document text
    • https://psychologgia.pl/Upload/file/13810887102.pdfIn PDF document text
    • https://israelonthehouse.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607fe874c5a20---6249489241.pdfIn PDF document text
    • https://alfa-pechati.ru/wp-content/plugins/super-forms/uploads/php/files/221d723f45e03cd65c9aab7e8700e812/23718330296.pdfIn PDF document text
    • http://salonlomi.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160b41ccd1c673---71085507692.pdfIn PDF document text
    • https://cmfnepal.org/userfiles/files/6232124159.pdfIn PDF document text
    • https://unicornproduction.gr/wp-content/plugins/super-forms/uploads/php/files/e30bf81639794ea6b24ad2eec104e7cd/58419235877.pdfIn PDF document text
    • http://www.peplex.it/wp-content/plugins/formcraft/file-upload/server/content/files/1606ebe9328847---xonajigen.pdfIn PDF document text
    • http://autoshiftbid.com/fckeditor/userfiles/file/funedemupijepokamamezijem.pdfIn PDF document text
    • http://promocode.lu/userfiles/files/64912614043.pdfIn PDF document text
    • http://trenermichal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160b363f6a60d1---71344061728.pdfIn PDF document text
    • https://cissud.eu/uploads/ck_editor/files/funebodexif.pdfIn PDF document text
    • http://www.radioemka.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b776d6be01---tumisow.pdfIn PDF document text
    • https://cafemocion.com/userfiles/file/83075500147.pdfIn PDF document text
    • https://brylka-kfz.de/wp-content/plugins/formcraft/file-upload/server/content/files/160f1278a81c6a---1771279115.pdfIn PDF document text
    • http://clarklawtexas.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/96781403758.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=manual+practico+de+psicoterapia+gestalt+angeles+martin+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_off00010f50.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F50 17584 bytes
SHA-256: 375926cab28d94d795d33e74c51735b332699e3aa883874314df85ba38f1bffb
font_01_sfnt_off00013c0d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13C0D 11056 bytes
SHA-256: a30c2a8a22e33f055f6c1b4d0c8a1352aa3aea7e816c712f683637dfb4a8518a
font_02_sfnt_off00015590.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15590 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1