Malicious PDF — malware analysis report

Static analysis result for SHA-256 d57d9bc49a3c74ef…

MALICIOUS

PDF

91.0 KB Created: 2021-08-11 20:52:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: fc5406f8a9310aa7262dd7c658d3da01 SHA-1: 7d9689690feeece754c4c6dd00279a84e69ce4cb SHA-256: d57d9bc49a3c74ef46f2846479ac506d7e0e60a9a3ef981091575b0bfde74198
156 Risk Score

Malware Insights

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

This PDF file was flagged by a machine learning classifier and ClamAV as malicious, indicating a high likelihood of malicious intent. The document contains numerous links, many pointing to compromised WordPress sites, which likely serve as a link farm to redirect users. This technique is commonly used for phishing or distributing further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://synerhu.ru/uplcv?utm_term=acido+citrico+formula+quimica PDF link annotation
    • https://nuregio.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b7e2e7debd9---xomirexunijafe.pdfIn PDF document text
    • https://chocoinmobiliario.com/wp-content/plugins/super-forms/uploads/php/files/7c3aeee122c58c48c15ce5b10f1c8e6d/98191019040.pdfIn PDF document text
    • https://samsunyapi.com/userfiles/files/fozazojemowu.pdfIn PDF document text
    • https://ltssinternational.com/res/wysiwyg/file/10543987196.pdfIn PDF document text
    • https://medosojewellery.com/userfiles/files/60892952435.pdfIn PDF document text
    • https://tenfci.org/userfiles/file/42195922124.pdfIn PDF document text
    • http://www.derbysignandgraphics.com/uploads/file/kibuwomenixiralozunumegaf.pdfIn PDF document text
    • http://regimhotelierbucuresti.com/images/userfiles/fefabapezalazobesoruzisan.pdfIn PDF document text
    • http://dichvugiayphep.biz/upload/ck/files/95100313260.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1606f24a6ead90---lowibozoro.pdfIn PDF document text
    • http://www.mezmat.ru/ckfinder/userfiles/files/69003173600.pdfIn PDF document text
    • http://www.sg-callenberg.de/wp-content/plugins/formcraft/file-upload/server/content/files/16074cb4daa043---kalososutimagofo.pdfIn PDF document text
    • https://detmers-kontejner.hr/files/gujewigujakivekug.pdfIn PDF document text
    • http://andlupa.com/userfiles/file/29883668421.pdfIn PDF document text
    • http://ptk-astana.kz/wp-content/plugins/super-forms/uploads/php/files/936c5e660604ac78f1e91e724b48eed4/fijonuvedetasipililazalet.pdfIn PDF document text
    • http://assushop.com/userfiles/assushop.com/file/50316706315.pdfIn PDF document text
    • http://lalitas-thaimassage-spa.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606e7270106fb---69657245636.pdfIn PDF document text
    • http://jhferry.com/data/fckeditor/file///fadululijuwi.pdfIn PDF document text
    • https://www.revistadefiesta.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aeb769f362e---73399636673.pdfIn PDF document text
    • http://alt-1c.ru/userfiles/file/7525847328.pdfIn PDF document text
    • https://fleschimmo.lu/userfiles/files/zorix.pdfIn PDF document text
    • https://singaporenotarypublic.com/wp-content/plugins/super-forms/uploads/php/files/65dc8c97843f47dd4c9cf7fe41dee66d/57748378114.pdfIn PDF document text
    • https://www.marvistasales.com/wp-content/plugins/super-forms/uploads/php/files/41f3b58eaaa3d3762986519eca48c6c5/bikomefajijamotepokodo.pdfIn PDF document text
    • https://www.apartamentselsllacs.com/wp-content/plugins/super-forms/uploads/php/files/5rr7irnc4oobe0o3d4eqlmgr6c/63099766577.pdfIn PDF document text
    • 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_off0000f869.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF869 10460 bytes
SHA-256: f743f9ad601d0858af128231c03769afdf5c2764eed4cf8fe25d1bfb4a2ebc60
font_01_sfnt_off00010ff6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FF6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012808.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12808 21116 bytes
SHA-256: bf57ac18441dc5c0ebf33da7693161436684f084ce68b62771b0c6c73c582ef4