Malicious PDF — malware analysis report

Static analysis result for SHA-256 d61fc485ba83bb3e…

MALICIOUS

PDF

81.6 KB Created: 2021-09-13 18:13:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 8114ff1456e980c51a14033218f78223 SHA-1: 5af12019bc9f1a26e7cd2a16f23da93ed059cac8 SHA-256: d61fc485ba83bb3e7503b7c60a4871e776575708b0a2152a65dd4e418dca7239
156 Risk Score

Malware Insights

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

This PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing or trojan delivery mechanism. It contains numerous links pointing to potentially compromised websites or disposable hosting, suggesting an attempt to redirect users to malicious content. The presence of multiple PDF link farm heuristics indicates a deliberate effort to obscure the final destination and distribute the malicious payload across various domains.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://ystechpro.com/nbloom/fckuploads/file/15046504644.pdf In PDF document text
    • http://www.fattyweng.com.sg/wp-content/plugins/formcraft/file-upload/server/content/files/1613424f9b5b4c---24606594561.pdfIn PDF document text
    • http://hoteldarim.ir/basefile/hoteldarimir/files/kazawonumopevigipibivira.pdfIn PDF document text
    • https://qamarapps.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f5d604a991---suxozogodi.pdfIn PDF document text
    • https://guijek.com/userfiles/file/tanumilikeso.pdfIn PDF document text
    • http://www.neslihanonur.com/wp-content/plugins/super-forms/uploads/php/files/caf61c5bda3012ee961b693b2eb559a9/8533429001.pdfIn PDF document text
    • http://www.tlo.ntou.edu.tw/ckfinder/userfiles/files/79222269794.pdfIn PDF document text
    • http://rollfactorytogo.com/uploads/files/62460711091.pdfIn PDF document text
    • https://hondamienbac.vn/userfiles/file/wifazu.pdfIn PDF document text
    • http://xedaptheduc.net/app/webroot/uploads/files/66826307397.pdfIn PDF document text
    • https://digireg.ru/upload/36255792496.pdfIn PDF document text
    • https://cooperadora.grupocreartel.com/documentos/archivos/22110687700.pdfIn PDF document text
    • https://imotrading.com/images/userfiles/posus.pdfIn PDF document text
    • http://samurairamenbar.com/uploads/files/55946451959.pdfIn PDF document text
    • http://albertf.madteam.net/ckfinder/userfiles/files/nofusugenugovosunaju.pdfIn PDF document text
    • http://novosib-sport.ru/ckfinder/userfiles/files/83674193024.pdfIn PDF document text
    • http://zavalinka.by/var/upload/file/51209091512.pdfIn PDF document text
    • http://dailynewsodia.com/assets/ckfinder/core/connector/php/uploads/files/90953566417.pdfIn PDF document text
    • http://businessdevelopmentcenter.pl/uploads/userfiles/files/88818986925.pdfIn PDF document text
    • https://stehovani-ostrava.cz/static_pages_files/file/43728645011.pdfIn PDF document text
    • http://www.c-l-r-p.com/admin/ckfinder/userfiles/files/birowevazixebax.pdfIn PDF document text
    • https://www.chablis-gautherin.com/ckfinder/userfiles/files/13641254746.pdfIn PDF document text
    • http://www.kreasoft.mx/wp-content/plugins/formcraft/file-upload/server/content/files/16135e63023984---xikujisunofevovut.pdfIn PDF document text
    • https://bizdrive.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/161327e5587c8c---53800198617.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=wifi+greyed+out+androidPDF 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_off0000d901.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD901 18516 bytes
SHA-256: a7a4de3ccedd9c6dcfe291df6dde308081f62e065820390ab8fce36bde7e6b77
font_01_sfnt_off000108f4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108F4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001210b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1210B 10520 bytes
SHA-256: f2e5a449c21a5c9e5b79f44f5a2ede048c070e2ff98cef3e21abc127cb10f89d