Malicious PDF — malware analysis report

Static analysis result for SHA-256 98b865465a606ecf…

MALICIOUS

PDF

81.4 KB Created: 2021-09-12 22:57:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: c7d955919992f185f74d92becc123fb6 SHA-1: bbbea9ffe4d2745c74d0354b4c0241a7ee2989a1 SHA-256: 98b865465a606ecf67bb607a54b32bc39891e2197f5982f2c8799d35c6aa77f6
114 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded JavaScript stream and multiple links, one of which is algorithmically generated and points to a PDF hosted on a suspicious domain. The ML classifier also flagged this PDF as malicious. The presence of embedded JavaScript suggests an attempt to execute malicious code, likely to download or redirect to further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 6

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://teen.plovdivweek.com/js/ckfinder/userfiles/files/68198715155.pdf In PDF document text
    • http://waetsukai.jp/system/ckfinder/userfiles/files/34588691210.pdfIn PDF document text
    • http://jobcred.com/rk/jobcred/uploads/image/file/82678833797.pdfIn PDF document text
    • http://evola.it/userfiles/files/zetikozakix.pdfIn PDF document text
    • https://enilubricantvn.hoakhanh.vn/uploads/image/files/67323057122.pdfIn PDF document text
    • http://simp-q.ru/userfiles/file/rawosi.pdfIn PDF document text
    • http://srs-budapest.hu/uploads/files/47952039074.pdfIn PDF document text
    • https://bank-kredit.at/ckfinder/userfiles/files/38488064732.pdfIn PDF document text
    • http://daydeothe.vn/rich_editor/file/70505557356.pdfIn PDF document text
    • https://cosanuesa.com/componentes/editor/ckfinder/userfiles/files/35567576156.pdfIn PDF document text
    • https://kottayammedicalcollege.org/CMS/ckfinder/userfiles/files/korupizowepawolos.pdfIn PDF document text
    • https://specialgarden.ro/userfiles/file/wazutewanazoga.pdfIn PDF document text
    • https://ontech.vn/images/ckeditor/files/peder.pdfIn PDF document text
    • https://assignmentmart.com/ckfinder/userfiles/files/10932736173.pdfIn PDF document text
    • http://futurepoolandspa.com/ckfinder/userfiles/files/76012416475.pdfIn PDF document text
    • https://madame-tina.com/ckfinder/userfiles/files/nubonatenufomeputejube.pdfIn PDF document text
    • https://pametnidom.hr/pametne_kuce/userfiles/file/7099852509.pdfIn PDF document text
    • http://ambulatorioveterinarioscapindandrea.it/userfiles/files/fufakavunubosesexa.pdfIn PDF document text
    • http://gaudi.tw/upload/file/71948618432.pdfIn PDF document text
    • https://baobiachau.com/luutru/files/27275713046.pdfIn PDF document text
    • https://myphi.biz/nbloom/fckuploads/file/pamudivitalesupes.pdfIn PDF document text
    • http://linuxnewyork.com/draft/media/94482101643.pdfIn PDF document text
    • http://2m-m.eu/userfiles/files/38824708152.pdfIn PDF document text
    • http://www.cafeinca.com/img/public/contenido/file/mekuluwovod.pdfIn PDF document text
    • https://festivalecolo.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16137b4a270663---fikekibipupamabafexibopij.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=ulnar+nerve+both+armsPDF 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_off0000dc18.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC18 10492 bytes
SHA-256: 4a2e3cfcb7eb5be6e8125e26fce53dcfa6878523a8b0e71e917051339c604806
font_01_sfnt_off0000f3d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3D0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010be2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10BE2 17052 bytes
SHA-256: dc961b8f0345cb19c057e718514f41ad34c16ddb5143ac0223ea338373b460c8