Malicious PDF — malware analysis report

Static analysis result for SHA-256 03cd02ca0bf37ebc…

MALICIOUS

PDF

85.6 KB Created: 2021-09-14 09:49:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: cdb9cadd104fa83aa1581aab9595b967 SHA-1: fce08d416abd16f0bd509c365867751e743baeee SHA-256: 03cd02ca0bf37ebcbd67fb22da4d9179e1d0075b9cd391e51a045cd1307f5d19
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to other PDF files hosted on various domains, indicating a link farm. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' strongly suggests this is for SEO manipulation or to distribute malicious content. While no scripts were explicitly extracted, the ML classifier and ClamAV detection indicate malicious intent, likely involving the exploitation of PDF vulnerabilities or the delivery of further payloads via the linked documents.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9970

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 http://seasonsblinds.com/uploads/ckfinder/userfiles/files/64624594931.pdf In PDF document text
    • http://tdvvietnam.vn/webroot/img/files/terofolajawetapevixikodip.pdfIn PDF document text
    • http://bigbulkbags.ahmadpackages.com/survey/userfiles/files/masitoxomumikitonulok.pdfIn PDF document text
    • http://kingkady.cn/uploadfile/files/46339328348.pdfIn PDF document text
    • http://geombiagioschettino.eu/userfiles/files/perexerokozowebupo.pdfIn PDF document text
    • http://acetuitioncentre.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16139dc6370c9d---20762598815.pdfIn PDF document text
    • https://lesartsdansmonjardin.com/userfiles/file/20210902145254.pdfIn PDF document text
    • https://washlounge.in/ckfinder/userfiles/files/mulemibemuga.pdfIn PDF document text
    • http://le-nora.com/userfiles/file/gijowumegubufesonine.pdfIn PDF document text
    • http://shijijiaming.cn/filespath/files/20210904215412.pdfIn PDF document text
    • http://gtlfuelmarine.com/userfiles/file/40036029144.pdfIn PDF document text
    • http://c-amc.com/upload/files/legivazetesidetavuwele.pdfIn PDF document text
    • http://anthonyvienna.com/sites/default/files/file/wonifimiminozevaw.pdfIn PDF document text
    • https://ruiguoex.com/upfile/files/2021/09/05/rodak.pdfIn PDF document text
    • http://xn----8sbfeahwarn6ac1adp3fb2p.xn--p1ai/userfiles/file/gafefafupigeju.pdfIn PDF document text
    • https://npkfertilizerproduction.com/d/files/tuwilotapasitukujowodisif.pdfIn PDF document text
    • http://studiomilano.eu/userfiles/files/12440726495.pdfIn PDF document text
    • http://corporatiegids.nl/uploads/files/1426928618.pdfIn PDF document text
    • http://mayxaydungthienlong.com/uploads/files/files/muwupuw.pdfIn PDF document text
    • http://www.rupankar.com/fckimages/file/xebosirekesipikosenifife.pdfIn PDF document text
    • http://thamcohoaian.com/webroot/img/files/tuxumufuwusino.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=the+little+engine+that+could+story+pdfPDF 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_off0000e802.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE802 18488 bytes
SHA-256: fc47b06781205ff1e6816c010ef92f0e5bdcf569aa0612531377222687068b66
font_01_sfnt_off00011764.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11764 11076 bytes
SHA-256: ae7df79f0625856d1bad89eba143f9a092d7437190106662bf72421d3dbc4d4f
font_02_sfnt_off00013100.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13100 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1