Malicious PDF — malware analysis report

Static analysis result for SHA-256 7935d8a4247d70d3…

MALICIOUS

PDF

80.7 KB Created: 2021-09-12 00:01:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: e6a889ac230fb7447be736142cad172a SHA-1: 0133aa2135fdc015c2f175527f9cb62dd3b2806e SHA-256: 7935d8a4247d70d3c5a609971d3035e3f3f64d5781ac2e062990ab7abe87e46c
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The ML classifier strongly indicated maliciousness, and the presence of external URIs and compromised CMS uploads further supports this assessment. No scripts were extracted from this sample, but the structure and URL distribution are indicative of a phishing or malware distribution lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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://oniceh.ru/uplcv?utm_term=chaos+road+combat+racing+mod+apk PDF link annotation
    • http://pericosrentcar.com.mx/wp-content/plugins/formcraft/file-upload/server/content/files/1613ae72eb08c7---nijasesexakepefurenav.pdfIn PDF document text
    • http://eastendmediation.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/wuxeturudukirejexipudotot.pdfIn PDF document text
    • https://veglifekc.org/wp-content/plugins/super-forms/uploads/php/files/pivumuk.pdfIn PDF document text
    • http://vivo-mebel.ru/upload/file/mefagowaso.pdfIn PDF document text
    • https://aynadakikemalizm.com/resimler/files/vofuwefarezonure.pdfIn PDF document text
    • http://aviatechinform.ru/sadm_files/22812128788.pdfIn PDF document text
    • http://tdjl.com/uploadfile/file///2021090202380718.pdfIn PDF document text
    • https://sportnazona.bg/f/uploads/files/tuzevizelurubumiromobu.pdfIn PDF document text
    • http://itcck.org/upload/editor/file/59822974295.pdfIn PDF document text
    • http://agriturismocorteerbatici.it/userfiles/files/difowitupotoxipuj.pdfIn PDF document text
    • https://miltonmattox.com/userfiles/file/30570278618.pdfIn PDF document text
    • http://meetburgerusa.com/uploads/files/farokoxe.pdfIn PDF document text
    • http://steelfurniturecn.com/d/files/16436173971.pdfIn PDF document text
    • http://zubrcup.by/files/files/75649933156.pdfIn PDF document text
    • http://birons.net/wp-content/plugins/super-forms/uploads/php/files/1751cf952e623c35f269a0bcc64dea88/bodef.pdfIn PDF document text
    • https://solucionaesp.com/ckfinder/userfiles/files/bigezitotubuje.pdfIn PDF document text
    • https://realxenon.ru/uploads/files/39075520758.pdfIn PDF document text
    • https://udachi.co.th/wp-content/plugins/super-forms/uploads/php/files/87ejm0bipavj841neb0bfoq1ag/12484221102.pdfIn PDF document text
    • https://thai-airpark.com/ckfinder/userfiles/files/82090033694.pdfIn PDF document text
    • https://namkhoasaigon.vn/web/images/files/4806437763.pdfIn PDF document text
    • http://ateliergermain.club/sites/default/files/file/ditowufazixowagovol.pdfIn PDF document text
    • https://parkettworld.com/upload/files/forewokuna.pdfIn PDF document text
    • https://santa.sg/images/users/00000000/files/87348005034.pdfIn PDF document text
    • https://loyd.rs/images/file/54185507833.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_off0000d71b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD71B 17452 bytes
SHA-256: d8c844f5090410ac81940d6ef0a72c0a1655ab9ceb6eaf83e1ffdbc36b66c150
font_01_sfnt_off00010410.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10410 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011c27.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C27 11048 bytes
SHA-256: 10e94d37c90e1a6194590de718a29a8ec820d0432f6740f071ac142eecfca665