Malicious PDF — malware analysis report

Static analysis result for SHA-256 2f4f2c26d227c2d2…

MALICIOUS

PDF

79.5 KB Created: 2021-09-16 00:44:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: f425b90ccbcbd2a1c22a2f415b2d9b10 SHA-1: c6e28459a4581a546ece76b03dfa13d44b61fdd0 SHA-256: 2f4f2c26d227c2d2294f8e326ab7d3b03462e0727458ae7ff1d58c5cfb5dc0a6
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous embedded URLs pointing to external PDF files, suggesting a link farm or redirection mechanism to distribute further malicious content. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating a pattern of using disposable hosting for these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 http://pcserviszlin.cz/ckfinder/userfiles/files/romemajoripigevuzusemefo.pdf In PDF document text
    • http://aedelsur.com/contenido/files/dawowuzenivi.pdfIn PDF document text
    • https://spacio.hk/attachment/file/folipulusex.pdfIn PDF document text
    • http://sancheonglittletheaters.com/upload/userfiles/2021/09/files/210912021002.pdfIn PDF document text
    • http://brenno-tojestto.pl/userfiles/file/98640583957.pdfIn PDF document text
    • http://praguetransfer.com/files/file/maziju.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140fe2080de0---97312762852.pdfIn PDF document text
    • http://huabulaw.com/uploadpic/2021-9/file/2021091000532873499.pdfIn PDF document text
    • https://krossi.ru/images/content/files/7036900905.pdfIn PDF document text
    • http://hoangnamjsc.com/upload/files/2464129716.pdfIn PDF document text
    • https://orig-shop-gsm.ro/ckfinder/userfiles/files/67003216950.pdfIn PDF document text
    • http://www.kinoimaging.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1614166f3d4adf---63515270362.pdfIn PDF document text
    • http://szamosiszerviz.hu/feltoltott/files/foxewukof.pdfIn PDF document text
    • https://coastalholidayproperty.com/ckfinder/userfiles/files/tufalavewerudadepage.pdfIn PDF document text
    • https://www.aifimm.it/admin/inc/ckfinder/userfiles/files/17262387503.pdfIn PDF document text
    • https://uclerbaklava.com/resources/file/ratanode.pdfIn PDF document text
    • https://artcorner-fiberglass.com/userfiles/files/wawivurojumetoxutofu.pdfIn PDF document text
    • http://robedecreateur.com/img/files/65888671864.pdfIn PDF document text
    • https://szabobuszberles.hu/files/files/68032965855.pdfIn PDF document text
    • http://k3projekt.pl/uploads/userfiles/files/8292647565.pdfIn PDF document text
    • https://lbjgold.in/ckfinder/userfiles/files/49173228624.pdfIn PDF document text
    • http://gamjagolla.com/uploads/files/1108155009.pdfIn PDF document text
    • https://wspaperbag.com/userfiles/file/54420307048.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=android+studio+read+json+filePDF 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_off0000d14e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD14E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e960.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE960 17840 bytes
SHA-256: 1bb5dd62c4413f3c791858073972589ae9473995c3f19d5b9de7c8e691420abb
font_02_sfnt_off00011817.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11817 10560 bytes
SHA-256: 123fa0907ff55f1aafcbfb04a7a1d01be4dfc4bb72331ae2b4f9872f3c052aac