Malicious PDF — malware analysis report

Static analysis result for SHA-256 fcc4582602bb47d4…

MALICIOUS

PDF

83.1 KB Created: 2021-09-19 02:11:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: e0e05c35c8825b6f194ea1e85f330435 SHA-1: ac6657f172923984248a35e67dc18eea1912d3d3 SHA-256: fcc4582602bb47d4c9b0a82a79f962253b70b2d8acd8781a19645dd9e686b4dc
106 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to other PDF files on disposable domains, indicating a link farm or redirection scheme. The ML classifier strongly flagged this PDF as malicious, and heuristics identified it as a link farm on disposable hosting. While no scripts were explicitly extracted, the nature of the links suggests a phishing or scam attempt to lure users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 5

  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://garglob.ru/uplcv?utm_term=what+is+the+best+free+voice+recorder+for+android PDF link annotation
    • https://nezrenpin.com/calisma2/files/uploads/58509682916.pdfIn PDF document text
    • http://tea-ra.com/user_data/upload/save_image/files/19068662608.pdfIn PDF document text
    • http://odesignlab.ru/admin/ckfinder/userfiles/files/zevimix.pdfIn PDF document text
    • https://intelean.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613cc3304580b---59906002596.pdfIn PDF document text
    • http://furkansigorta.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1613963593c7a2---26353131168.pdfIn PDF document text
    • http://shijijiaming.cn/filespath/files/20210903103005.pdfIn PDF document text
    • http://unitec-egypt.net/userfiles/file/86918590641.pdfIn PDF document text
    • https://ytdrive.com/CKEdit/upload/files/71892224248.pdfIn PDF document text
    • http://alfavit.tv/userfiles/file/xinati.pdfIn PDF document text
    • http://auburn-properties.com/userfiles/files/kidagi.pdfIn PDF document text
    • http://assotechne.eu/userfiles/files/57813785130.pdfIn PDF document text
    • http://zatoodesign.com/userfiles/files/21809951723.pdfIn PDF document text
    • http://turnwealthy.com/ckfinder/userfiles/files/81673294844.pdfIn PDF document text
    • https://mokhalasati.com/userfiles/files/jepamewenaxesizokene.pdfIn PDF document text
    • http://kangmeideyiliao.com/uploadfile/file///2021091614561557.pdfIn PDF document text
    • http://61kidsclub.com/userfiles/file/31808983340.pdfIn PDF document text
    • https://nacionalequipamentos.com/ckeditor/uploads/files/muzivitikafalalej.pdfIn PDF document text
    • http://nanoscopy.ru/uploads/files/60973970726.pdfIn PDF document text
    • http://ateliergermain.net/sites/default/files/file/dolagukano.pdfIn PDF document text
    • https://techinnsrl.com/writable/public/userfiles/file/mokezugafixejatawuni.pdfIn PDF document text
    • http://studiomedicoveterinariobellucci.eu/userfiles/files/gosedat.pdfIn PDF document text
    • https://bloomeng.com/uploads/kolopav.pdfIn PDF document text
    • http://www.de.ruben.pl/ckfinder/userfiles/files/maxatat.pdfIn PDF document text
    • http://novelinternationalschool.com/ckfinder/userfiles/files/39073440716.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_off0000e1ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1EC 16824 bytes
SHA-256: 8b2b839c7867a6d5f444a422b75b04b3ad4f0d5dd41e1c3a64515de742ecb0e0
font_01_sfnt_off00010d4e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D4E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012565.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12565 10724 bytes
SHA-256: 19cb90e09185b1c76f8417b074f73191cde1efac9de6a0d134b6c610ee0b5fb6