Malicious PDF — malware analysis report

Static analysis result for SHA-256 2f08acb57e415e43…

MALICIOUS

PDF

82.0 KB Created: 2021-09-19 22:10:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: ec066a4a6d9b823a5ec1d7680377979a SHA-1: 0f5fcdd19a7bf9d359d9b64a79b126b8ac454369 SHA-256: 2f08acb57e415e438e0b091fe18eae70828000847ff5c05545ade39a3f919322
96 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to disposable hosting or compromised CMS upload directories, indicating a link farm or redirection scheme. The ML classifier strongly flagged this PDF as malicious. The presence of multiple PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics further supports the conclusion that this document is designed to direct users to potentially harmful external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

Heuristics 5

  • 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://ms01bet.com/contents/files/kawej.pdf In PDF document text
    • http://etyekilovarda.hu/userfiles/file/bafogixedasulato.pdfIn PDF document text
    • https://icbacademy.com/upload/files/22243249651.pdfIn PDF document text
    • https://costabravas.com/uploads/localidades/files/26916907068.pdfIn PDF document text
    • https://kme.pl/global/app/webroot/uploads/file/16305254266309.pdfIn PDF document text
    • https://caror.hu/ckfinder/userfiles/files/zitefegeb.pdfIn PDF document text
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/16133faf5cdc60---lesipojatusarejowo.pdfIn PDF document text
    • https://anzhero-sudzhensk.verlauf-ekb.ru/admin/ckfinder/userfiles/files/jujuwurejaledukuvaj.pdfIn PDF document text
    • https://corianderedmonton.com/ckfinder/userfiles/files/fuzadorup.pdfIn PDF document text
    • http://www.mkkdigital.pt/wp-content/plugins/formcraft/file-upload/server/content/files/161456349c6a5b---doxepigibizarofejuwewolil.pdfIn PDF document text
    • http://studiozammuner.eu/userfiles/files/nazebufuxunabuxifowiros.pdfIn PDF document text
    • http://wxmx.cn/upload/ckimg/files/202109110230369711.pdfIn PDF document text
    • https://vashadvokat82.ru/wp-content/plugins/super-forms/uploads/php/files/ec6696d1f939f92f2e40ec8f14f38482/28464918512.pdfIn PDF document text
    • http://asesorgubernamental.com/images/file/vimuvewefagafe.pdfIn PDF document text
    • http://cppzone.ru/users/blogs/file/wajefuwepukuv.pdfIn PDF document text
    • http://bebelino.ru/userfiles/file/fegezulanopeli.pdfIn PDF document text
    • http://www.blackhillsdancecentre.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613850b124697---neregukumiwuxi.pdfIn PDF document text
    • http://fasson.vip/images/editor/files/lomini.pdfIn PDF document text
    • https://kotata-zlin.cz/obr/clanky/file/dodikupuza.pdfIn PDF document text
    • http://heaig.org/editor/ckfinder/userfiles/files/taxosezigavifizozi.pdfIn PDF document text
    • http://groupkaishan.com/d/files/39060557764.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=stylish+font+apk+downloadPDF 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_off0000d494.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD494 10728 bytes
SHA-256: 56657444c346e46b845ace27b34342948370c5d0502f6cd173c507a870ef7340
font_01_sfnt_off0000ed34.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED34 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010546.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10546 20732 bytes
SHA-256: ff9cb99cf674dca83de32de0fcc9860554f2b61ff33856ed84225208bed141c4