Malicious PDF — malware analysis report

Static analysis result for SHA-256 3c457338406c45ca…

MALICIOUS

PDF

76.8 KB Created: 2021-07-17 06:53:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: ad5fba29bd425dd1e38fa54a02008e65 SHA-1: 88509f604d0a406d8da0cd46cbfcea9324d0ded6 SHA-256: 3c457338406c45cad1a145150d2d8d1b9dd3e64c4b2221b0525eb9f6b3559ed0
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links pointing to compromised CMS upload storage and disposable hosting, indicating a link farm designed to redirect users to potentially malicious sites. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and link farm heuristic point towards an attempt to lure users to external resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://czdashan.cn/uploadfile/file/2021061216300473499.pdf In PDF document text
    • http://www.contectrade.hu/fckfiles/file/48648876879.pdfIn PDF document text
    • http://championshipsportsrings.com/clients/23492/File/xomerovunaparudu.pdfIn PDF document text
    • http://veronicanealhome.com/wp-content/plugins/formcraft/file-upload/server/content/files/2/160a0160022980---18827009540.pdfIn PDF document text
    • https://realwebguys.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608214210bfd4---gotawonekojiju.pdfIn PDF document text
    • https://brunoamaranti.it/wp-content/plugins/super-forms/uploads/php/files/dlrddkacrbkt7a8b2bnuljrv56/fofuse.pdfIn PDF document text
    • https://loan-financial.com/wp-content/plugins/super-forms/uploads/php/files/2fbaaf07568bfb9ceac929ffb009c2eb/67197243007.pdfIn PDF document text
    • http://ruresept.ru/files/file/36200168229.pdfIn PDF document text
    • https://primeodontorj.com/wp-content/plugins/super-forms/uploads/php/files/7e517aa25853c036a88b78ef6fe412f0/jiwomoso.pdfIn PDF document text
    • https://www.toptalentusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083f913a4d9a---mefapizisubenerobopom.pdfIn PDF document text
    • http://sneedfamilyct.com/clients/44919/File/1345187008.pdfIn PDF document text
    • https://www.denisonlandscaping.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f35e1c5c3d---sawewifekaz.pdfIn PDF document text
    • http://www.drop-lok.com/wp-content/plugins/formcraft/file-upload/server/content/files/160773c8fa39c3---kigavebuxunomumerimila.pdfIn PDF document text
    • https://sarujiovalente.com/wp-content/plugins/super-forms/uploads/php/files/7341llvcduh32jhu4km739t6lu/gerakiwo.pdfIn PDF document text
    • http://www.infranetltd.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083bb388f76d---magejebewimiletivujapita.pdfIn PDF document text
    • http://www.finanzanlagen-honorarberatung.de/wp-content/plugins/formcraft/file-upload/server/content/files/16086d465ca9fc---31024483878.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e98078e2834---zawijifetufepibiwi.pdfIn PDF document text
    • https://tidurmalam.com/contents//files/31588280338.pdfIn PDF document text
    • http://www.iycadana.org/wp-content/plugins/super-forms/uploads/php/files/vccnj1gk4b2lpvhunt1j4mlkq1/97443261698.pdfIn PDF document text
    • http://naitikfashions.com/ckfinder/userfiles/files/98279359697.pdfIn PDF document text
    • https://doellefjelde-mussemarked.dk/images/newsmail/file/wuseluzak.pdfIn PDF document text
    • http://mfplus.ba/wp-content/plugins/formcraft/file-upload/server/content/files/160884bb99a032---jegupebux.pdfIn PDF document text
    • http://baigeleather.com/userfiles/file/77436222835.pdfIn PDF document text
    • http://dolinakrzeptowa.pl/public/upload/ckfinder//userfiles/files/50574659329.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=to+give+honorPDF 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_off0000cc8a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC8A 16932 bytes
SHA-256: 283516a2113f0da797f39370979741f0c8eb138ecba3e2d3d8a706fce71a56bb
font_01_sfnt_off0000f893.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF893 9940 bytes
SHA-256: db1e64b6761840901125dfbfe898ac5bb7f52b61d44c965e7e1f2ddb94e82aec
font_02_sfnt_off00010e7e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E7E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1