Malicious PDF — malware analysis report

Static analysis result for SHA-256 bd845ef5624a1383…

MALICIOUS

PDF

71.7 KB Created: 2021-09-08 13:42:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: cd00d7884b24dad24b01b04b1f578c4f SHA-1: 7e58b170f2335ce6a46c8b105de1c05ee02a8880 SHA-256: bd845ef5624a1383ddc762768186eae0547b849c3086f30007c42fa8fa5f707b
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as a malicious PDF by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous embedded URLs pointing to external domains, suggesting a phishing or malware distribution scheme. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this by identifying the PDF as a link farm on disposable hosting, likely to obscure the true malicious destination.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9916

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://crewmak.ru/uplcv?utm_term=3d+bioprinting+pdf PDF link annotation
    • http://smirna.pl/files/file/9121622543.pdfIn PDF document text
    • http://yousefmaktabi.com/ckfinder/userfiles/files/91707735379.pdfIn PDF document text
    • http://stringquartet.biz/web/images/fck/file/7012485797.pdfIn PDF document text
    • https://protectname.xyz/whoisprivacy/userfiles/files/15264065602.pdfIn PDF document text
    • http://marleenjansen.nl/images/uploadfiles/teginolatumuladuvipigazux.pdfIn PDF document text
    • http://colokit.thienlonggroup.com/Images_upload/files/rafokezepafaxowe.pdfIn PDF document text
    • http://bunny888.com/ckfinder/userfiles/files/53123524026.pdfIn PDF document text
    • https://sk-developers.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613748dd05615---norudexuvebofufe.pdfIn PDF document text
    • https://tutorsbureau.net/userfiles/file/71265328914.pdfIn PDF document text
    • https://alubiasdetolosa.com/files/galeria/files/47224523395.pdfIn PDF document text
    • https://albertoangel.sinecsas.com/ckfinder/userfiles/files/vakeguvota.pdfIn PDF document text
    • https://briljant-maleri.se/UserFiles/files/89012200700.pdfIn PDF document text
    • https://cristalparkhotel.com.ve/ckfinder/userfiles/files/87481570470.pdfIn PDF document text
    • http://www.la-rocca.pl/app/webroot/files/files/toxebametuxejire.pdfIn PDF document text
    • http://www.icf-plant.com/files/file/begezumivazej.pdfIn PDF document text
    • http://www.ocptecnology.com/admin/uploaded/fck/file/vozodivekuxadudolasofegi.pdfIn PDF document text
    • https://basisnomor.com/contents/files/gemaxo.pdfIn PDF document text
    • https://derechosenred.org/aym_image/files/13705441519.pdfIn PDF document text
    • http://toszegisuli.hu/userfiles/file/1974212944.pdfIn PDF document text
    • http://vsrru.ru/userfiles/file/84075214126.pdfIn PDF document text
    • https://gulfsupremesa.com/ckfinder/userfiles/files/58133714105.pdfIn PDF document text
    • https://halead.com/uploadfile/1630700384.pdfIn PDF document text
    • http://laptopcuhaiphong.vn/upload/files/85364463716.pdfIn PDF document text
    • https://33mobility.net/uploads/files/jigivomematix.pdfIn PDF document text
    • http://manpukulivermore.com/uploads/files/72476334549.pdfIn PDF document text
    • http://ahjygjg.com/upload_fck/file/2021-9-6/20210906072804806374.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_off0000bb24.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBB24 15396 bytes
SHA-256: e1ab062e61391c17c7b7fd5cfaefaffdfc77844b391467050263e221619b6c90
font_01_sfnt_off0000e1f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1F9 10380 bytes
SHA-256: 5643e2e46674a47836a11b65bd64862aa23152641c40535386d8a5db6928a9c3
font_02_sfnt_off0000f90a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF90A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1