Malicious PDF — malware analysis report

Static analysis result for SHA-256 234a0731f26d8fa2…

MALICIOUS

PDF

86.5 KB Created: 2021-08-29 18:04:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 1ce4f7a6fa343185326b95c6177bedab SHA-1: 47cc590ad791dba17b84dc15137b89933a3abee9 SHA-256: 234a0731f26d8fa2b18564f40104450181489e33920ea90cd7d52ace77afacef
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links to external websites, many hosted on potentially compromised or disposable domains, suggesting a link farm or phishing lure. The PDF structure and embedded URLs point towards an attempt to redirect users to malicious content, possibly for further exploitation or credential harvesting.

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 http://saikunghouse.hk/userfiles/983872035.pdf In PDF document text
    • http://fruitvita.com/files/files/pifirarikelolatur.pdfIn PDF document text
    • http://yearbookplus.com/uploads/ckfinder/files/milatakovomitevexisuj.pdfIn PDF document text
    • https://www.booster-p.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e579aa489d---voraxo.pdfIn PDF document text
    • https://peiitw.com/Upload/ckeditor/files/72930104774.pdfIn PDF document text
    • https://aradovan.com/userfiles/file/tafizutuzapugobopi.pdfIn PDF document text
    • https://cvsc.co/userfiles/file/mavudupusud.pdfIn PDF document text
    • http://srtcivilnorth.com/ckeditor_file/files/gewimufizixo.pdfIn PDF document text
    • http://nadiadsa.org/userfiles/file/9705323949.pdfIn PDF document text
    • https://manualismedicina.hu/fileok/file/19411968997.pdfIn PDF document text
    • https://prikolnaya.com/wp-content/plugins/super-forms/uploads/php/files/cb9b17abbbf17c4686d6e81957e3d81e/1010243476.pdfIn PDF document text
    • https://fastcomputer.vn/wp-content/plugins/super-forms/uploads/php/files/2196facff0d215f7223363c22a7de392/xiwunulodunadexadi.pdfIn PDF document text
    • https://www.sir.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1606c8a7d28dc5---45258271415.pdfIn PDF document text
    • https://www.delaneyllc.com/ckfinder/userfiles/files/tapolapipuzirizujiraxu.pdfIn PDF document text
    • http://belst.by/upload/file/mivuzopujolubuxoko.pdfIn PDF document text
    • https://steammining.com/userfiles/file/rafotuwufifopav.pdfIn PDF document text
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/160b00e8512072---73820168625.pdfIn PDF document text
    • http://kppzp.pl/userfiles/file/tenonaterajegudijo.pdfIn PDF document text
    • https://ijp2.com/contents/files/44423345232.pdfIn PDF document text
    • https://cosplay-expo.it/ckfinder/userfiles/files/jotepasosizivibi.pdfIn PDF document text
    • https://bamor.org/userfiles/file/37877654919.pdfIn PDF document text
    • https://greenbins.ca/ckfinder/userfiles/files/2798704724.pdfIn PDF document text
    • http://www.europesolidaire.eu/userfiles/files/getidewa.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=benefit+of+readingPDF 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_off0000ed98.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED98 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000105aa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105AA 18700 bytes
SHA-256: 7ff13612fb132d3ef8b5608638142b82bf1aaf912dc05f6683ec03724f19b56d
font_02_sfnt_off000134e5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x134E5 10368 bytes
SHA-256: 7a03de92760d22cc494c2c3eb48e8ae693a856037eb93f366ca0fe2a33e7aa5e