Malicious PDF — malware analysis report

Static analysis result for SHA-256 9bd838b566faa6a0…

MALICIOUS

PDF

80.4 KB Created: 2021-09-03 00:19:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: b7970614422e02fe8a937e8ec7623233 SHA-1: 20afec33a2039cef8b24d7b4b79f51bd0af65c27 SHA-256: 9bd838b566faa6a011dfb449e45d66e83bef1e41ff801e77f4bb1e971c1b8c82
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous links to compromised WordPress sites and disposable hosting, indicating a link farm designed to redirect users. The ML classifier strongly suggests malicious intent. While no scripts were directly extracted, the structure and URL patterns are consistent with phishing or malware distribution lures, likely delivered via spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://carthink.org/wp-content/plugins/formcraft/file-upload/server/content/files/160b725b1c8627---madimakov.pdf In PDF document text
    • http://kuehllawpc.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/daxaxiwevavamupupepine.pdfIn PDF document text
    • https://frasertechno.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e0686876e18---xonovunuruviditeliwopi.pdfIn PDF document text
    • http://thunderstar.cn/userfiles/file/20210828055320605485692.pdfIn PDF document text
    • http://flomojapan.com/upload/files/63639314885.pdfIn PDF document text
    • http://www.musicmaestrodiscos.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1608c2a414322d---66041947552.pdfIn PDF document text
    • http://xahuaheng.cn/userfiles/file/40657591012.pdfIn PDF document text
    • https://www.kiteschule-eckernfoerde.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a80d6c6622e---12648001387.pdfIn PDF document text
    • http://jedwines.com/cmsCart//upload/file/kizuropinuwamedelazuf.pdfIn PDF document text
    • https://anfauglir.com/images/file/4146818010.pdfIn PDF document text
    • https://hafa-verein.de/wp-content/plugins/super-forms/uploads/php/files/b9c28328672fade4958d93529c61a8dc/44048498617.pdfIn PDF document text
    • https://aawyx.com/sites/default/imageuser/file/futojupezegevewon.pdfIn PDF document text
    • http://www.leesii.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070fa74c8843---67071002634.pdfIn PDF document text
    • http://kuhomania.ru/ckfinder/userfiles/files/mawapitolexalutuletolavi.pdfIn PDF document text
    • http://shsuorui.com/uploadfiles/fckeditor/20210626/file/16247346745794.pdfIn PDF document text
    • https://capitalsyndic.com/userfiles/file/38313188446.pdfIn PDF document text
    • http://amexeuro.com/an3_Uploads/file/46701465864.pdfIn PDF document text
    • http://sangtaoad.com/uploads/userfiles/file/59243509207.pdfIn PDF document text
    • http://www.grupohk.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607080eb7dca2---gobixebidonolivalopejorur.pdfIn PDF document text
    • http://www.fattyweng.com.sg/wp-content/plugins/formcraft/file-upload/server/content/files/160a465f2ad1f6---desagaguk.pdfIn PDF document text
    • http://ytovietnam.net/ckfinder/userfiles/files/govutiz.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=kogan+smart+tv+dongle+manualPDF 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_off0000d64c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD64C 10656 bytes
SHA-256: 38806a079d8f9b47c52d41c22dace347b7a9afe06ca6616a60780a56359f6f4a
font_01_sfnt_off0000ee8c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE8C 17752 bytes
SHA-256: 61fcb75d48c795247bcf4be76713b16780827ed64bb7fa68af9942af20605f8e
font_02_sfnt_off00011c5d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C5D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1