Malicious PDF — malware analysis report

Static analysis result for SHA-256 df659355835068ba…

MALICIOUS

PDF

68.1 KB Created: 2021-09-25 10:49:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 52f5de1458d286c605ccb35c02490525 SHA-1: 39de1f3592ddc741a20d6b0f644c01502e020cbd SHA-256: df659355835068ba87f87558d460f23b4139ec1988cb480fe59262b550c7f3a8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Numerous heuristics indicate the PDF acts as a link farm, directing users to compromised CMS uploads and disposable hosting sites. The presence of embedded URLs further supports the attack pattern of redirecting users to potentially harmful external content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://oniceh.ru/uplcv?utm_term=pokemon+best+gba+games PDF link annotation
    • http://tucholainfo.pl/userfiles/file/8634795990.pdfIn PDF document text
    • https://ppkh.net/userfiles/file/37638095433.pdfIn PDF document text
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1612f94d38718d---tojubezezalideladifafeko.pdfIn PDF document text
    • https://nhaban24h.com.vn/wp-content/plugins/super-forms/uploads/php/files/f7ndvcqvkctf2bmbhli7l5qesk/wopor.pdfIn PDF document text
    • http://bannhuaduong.net/upload/files/80066711661.pdfIn PDF document text
    • http://disonde.com/filespath/files/20210912045247.pdfIn PDF document text
    • http://madang.eu/f_pds/fck/file/jixebakanuzume.pdfIn PDF document text
    • https://ekselantechnology.solutions/ckfinder/userfiles/files/71601494493.pdfIn PDF document text
    • http://novena99.com/uploads/files/202109020726456241.pdfIn PDF document text
    • http://gianenricofabro.com/userfiles/files/48835356021.pdfIn PDF document text
    • http://inewbus.com/wp-content/plugins/super-forms/uploads/php/files/qhjge55drv833vcfutq4ded5h5/kasukenawanopedididazimi.pdfIn PDF document text
    • http://adwokaci-pila.pl/userfiles/file/wipula.pdfIn PDF document text
    • http://tungalag.mn/userfiles/files/73991961093.pdfIn PDF document text
    • http://isystemlab.com/admin/ckfinder/userfiles/files/fobop.pdfIn PDF document text
    • http://madurastones.com/userfiles/file/jupuzidisofodetixigugaz.pdfIn PDF document text
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/hiruad2qm9k79arufhl3mhfij1/zazewabegofakobur.pdfIn PDF document text
    • http://summitremodelinginc.com/userfiles/files/vababarebukepa.pdfIn PDF document text
    • http://bjoybrands.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613748da5b3c5---4142620243.pdfIn PDF document text
    • https://www.netcorp.hu/data/editorfile/28232470462.pdfIn PDF document text
    • https://doellefjelde-mussemarked.dk/images/newsmail/file/geredixebopi.pdfIn PDF document text
    • https://angkaganjil.com/contents/files/77327794024.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_off0000ac08.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAC08 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c41f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC41F 10444 bytes
SHA-256: 1d8b07c8562e72f6cfb3710d42d31aaaaeb35dec85615ac4a884b610b4e1eb02
font_02_sfnt_off0000dbe1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBE1 15720 bytes
SHA-256: a2bb45c07e55ccc84e588d6cdae48c111376b1785aaa918d74c8723099c94444