Malicious PDF — malware analysis report

Static analysis result for SHA-256 e4cf13a839377a9a…

MALICIOUS

PDF

75.4 KB Created: 2021-09-16 15:50:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: fae120d4c717d21605524df40cf5619c SHA-1: 6bd6c3c96b90f35a2f96fcdf1ee917674ed971b1 SHA-256: e4cf13a839377a9aacad443674f86e34f50bb40dcfffdf9a87cc80cd11d2efe7
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier, indicating malicious intent. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic and the presence of numerous embedded URLs suggest a phishing or malware distribution campaign. While no scripts were extracted, the structure and embedded links point towards a malicious document designed to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://kdwatch.net/upload/files/2021090610005111.pdf In PDF document text
    • http://www.drop-lok.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133623ce9001---91660963980.pdfIn PDF document text
    • https://aradmissions.com/ci/userfiles/files/79548298285.pdfIn PDF document text
    • http://kriosispl.com/cote_dor_import/admin/ckfinder/userfiles/files/kitumokitowudawowixupe.pdfIn PDF document text
    • http://thietkewebbacninh.com/webroot/img/files/kozenum.pdfIn PDF document text
    • https://limpiezasinasel.com/userfiles/files/gizijiferuwup.pdfIn PDF document text
    • http://habitat3.eu/userfiles/files/rijatonusapefupagab.pdfIn PDF document text
    • http://chiangmaicharmingtravel.com/ckfinder/userfiles/files/tikireloxazeselujugev.pdfIn PDF document text
    • http://richmore.kr/uploadfile/fckeditor/file/zavarenobibezabawunaforuv.pdfIn PDF document text
    • http://montaze.org/democms/userfiles/file/gajufemat.pdfIn PDF document text
    • http://zxpgw.com/userfiles/file/2805311146.pdfIn PDF document text
    • http://cementfeet.com/userfiles/file/xivedanabimobazeme.pdfIn PDF document text
    • http://amblesidewindermere.ca/fckuploads/images/file/58157836404.pdfIn PDF document text
    • https://digireg.ru/upload/wesibosonaxigaxosol.pdfIn PDF document text
    • https://www.soroptimist.be/oldsite/intranet/ckeditor/ckfinder/userfiles/images/files/23839334164.pdfIn PDF document text
    • http://iaestedresden.de/userfiles/file/linepasif.pdfIn PDF document text
    • http://aybar-gallery.com/userfiles/files/kasakarugi.pdfIn PDF document text
    • http://pwmtqatar.net/userfiles/file/xozijidizanisitojopula.pdfIn PDF document text
    • https://sportsht.com/userfiles/file/91003289251.pdfIn PDF document text
    • http://immodraft.de/images/architekten_agentur_images_/file/rineduxekukalebeguxujo.pdfIn PDF document text
    • http://novaserv.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131b7c643974---9277899920.pdfIn PDF document text
    • https://gulfsupremesa.com/ckfinder/userfiles/files/51090746876.pdfIn PDF document text
    • https://idea-web.ro/app/webroot/files/userfiles/files/mimadubunodogelazesebab.pdfIn PDF document text
    • http://struttur-arch.it/userfiles/files/fexurifena.pdfIn PDF document text
    • http://precisionsurgicalworks.com/alpha/ckfinder/userfiles/files/lenute.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=the+worlds+hardest+game+4PDF 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_off0000c2b5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC2B5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000dacc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDACC 10628 bytes
SHA-256: e42c300fc6e805593fdb53ba9d40c714e440c6f4cf945eb1a5237cdbdc0fc2a3
font_02_sfnt_off0000f30c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF30C 17472 bytes
SHA-256: e9779b6e35aa70359ef1c5bbf70ae932506cf8ec6ed9231691bfe9f336d0ddc0