Malicious PDF — malware analysis report

Static analysis result for SHA-256 523191d773877c8b…

MALICIOUS

PDF

86.3 KB Created: 2021-08-10 21:22:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 1c340fa5fe1e1fa583136142fa4d760c SHA-1: e2f4d295bcb36db704e9863e6386e40ce7d585ca SHA-256: 523191d773877c8b03d2a7eb76fd35b2ed32e1617dbab63b6be9e977d42af83c
156 Risk Score

Malware Insights

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

The PDF contains a link farm with numerous URLs hosted on compromised CMS platforms, indicating a phishing or malware distribution attempt. ClamAV detection and ML classification confirm its malicious nature. The sample's structure and URL patterns suggest it is designed to lure users into clicking malicious links, potentially leading to further compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9957

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://churchosonline.com/wp-content/plugins/super-forms/uploads/php/files/50525722062147216080c67e69da53b4/nasukiwagisimaxijexogo.pdf In PDF document text
    • https://mzlpro.com/web/img/podborky/files/85066639324.pdfIn PDF document text
    • http://beveragesgs.com/userfiles/file/46482287635.pdfIn PDF document text
    • https://stef-nancy.fr/upload/document/56349644561.pdfIn PDF document text
    • http://donghocitizenchinhhang.com/uploads/userfiles/file/gakatal.pdfIn PDF document text
    • http://www.oschouston.com/osc/wp-content/plugins/formcraft/file-upload/server/content/files/161119617e6c83---49954093406.pdfIn PDF document text
    • http://kirilmazbardak.com/userfiles/file/32703078491.pdfIn PDF document text
    • https://baconbites.com/wp-content/plugins/super-forms/uploads/php/files/d35s4r7e03618lun64b7n868u0/vogizixapibupulilepalori.pdfIn PDF document text
    • http://tea-ra.com/user_data/upload/save_image/files/jolerofujamidewetotel.pdfIn PDF document text
    • https://qamarapps.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082760be4f20---69737843500.pdfIn PDF document text
    • http://jsushibrea.com/uploads/files/33313675583.pdfIn PDF document text
    • https://aartipalette.com/userfiles/file/41694953460.pdfIn PDF document text
    • https://www.superioreagle.com/wp-content/plugins/formcraft/file-upload/server/content/files/160afa383db45c---gamogogalekerefewatoj.pdfIn PDF document text
    • https://aliencosmicexpo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608394521000a---sujuliji.pdfIn PDF document text
    • https://internationalmedia.com/userfiles/file/loveb.pdfIn PDF document text
    • http://bizbecho.com/pa/trainstation/uploads/image/file/vusofadozazijunulufev.pdfIn PDF document text
    • https://www.chauffeur-prive-nice.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1608d38d03040e---zawiwupe.pdfIn PDF document text
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/1aa169b2b6db685b9f989b91be9ab7e2/81195198391.pdfIn PDF document text
    • http://arch-teh.com/pic/userfile/38683929091.pdfIn PDF document text
    • http://hasici-pristroje-eshop.cz/files/file/39457376407.pdfIn PDF document text
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e168f395a9.pdfIn PDF document text
    • http://onestep-tokyo.com/userfiles/file/39572019481.pdfIn PDF document text
    • http://moderncarrent.com/user_img/files/26311548858.pdfIn PDF document text
    • https://www.idahomedia.com/wp-content/plugins/super-forms/uploads/php/files/b7db200d8ddd5ed1964577ae72493e29/63290676201.pdfIn PDF document text
    • https://www.indee-r.fr/wp-content/plugins/super-forms/uploads/php/files/9d52daa3203ea7b363188c60fc4e78b4/69538102615.pdfIn PDF document text
    • https://www.sadcmedia.com/wp-content/plugins/super-forms/uploads/php/files/am1vjqis5dkq06lmkpcffaun1l/tebevopakapejifatux.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=origami+lotus+flower+easy+instructionsPDF 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_off0000ec17.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC17 11004 bytes
SHA-256: 4dd1bee17df4bfa4ff2c14127b1c474de306b422c295c7c67664b21800db0c64
font_01_sfnt_off000105d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105D0 17244 bytes
SHA-256: a1a59efa967acf19f51326af0300d637c6b93a368199df52da08363fc283a0e3
font_02_sfnt_off00013275.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13275 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1