Malicious PDF — malware analysis report

Static analysis result for SHA-256 a4a2c5cb5259a776…

MALICIOUS

PDF

81.9 KB Created: 2021-09-13 03:07:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 2014892d815f55a7f1df672e77673be6 SHA-1: 61bcf428f19085da600501c1f6ed352dcab9c5e7 SHA-256: a4a2c5cb5259a776da3f47f118539a32d30d2efd83b84fdc3b0abac685e4d5d9
66 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous embedded URLs, many of which point to suspicious domains and appear to be part of a link farm. The ML classifier strongly indicated maliciousness, and the heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' confirms the suspicious nature of the links. No scripts were extracted, but the structure suggests a malicious document designed to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 4

  • 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://ikomsolutions.com/admin/userfiles/file/zelojibulazagenefa.pdf In PDF document text
    • http://bigyikesmedia.com/home/xtremweb/public_html/consultinstitute/web/upload/files/92115243025.pdfIn PDF document text
    • http://newgatedesign.com/Images_upload/files/17772870977.pdfIn PDF document text
    • https://icbacademy.com/upload/files/49493164252.pdfIn PDF document text
    • http://telecycling.info/files/file/37491805447.pdfIn PDF document text
    • http://skupka23.ru/upload/m/33220521682.pdfIn PDF document text
    • https://aldaserwis.pl/ckfinder/userfiles/files/kipenutavazotobupasa.pdfIn PDF document text
    • http://szentistvanpatika.hu/upload/file/86362466096.pdfIn PDF document text
    • https://footballsod.com/images/ck-uploads/files/29334560660.pdfIn PDF document text
    • http://seoulsquare.com/userfiles/file/43986060730.pdfIn PDF document text
    • https://hetodon.com/fckeditorfiles/file/pezajukijet.pdfIn PDF document text
    • http://extintoresorigen.com/images/editor/ridivezonepova.pdfIn PDF document text
    • https://nhahangthanghuong.com/uploads/files/31724246903.pdfIn PDF document text
    • https://rumusjitu.com/contents/files/75209830151.pdfIn PDF document text
    • https://ms2gacor.com/contents/files/kejagiterarigaroko.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/161391c26e6ca2---jekuz.pdfIn PDF document text
    • http://condominiobrisasdelnorte.com/userfiles/file/42949109617.pdfIn PDF document text
    • http://yuhao-tech.com/userfiles/file/sosagalojewinul.pdfIn PDF document text
    • https://grandiosieventinuziali.it/filesUploads/file/90494356852.pdfIn PDF document text
    • http://tmkb.org.tr/ckfinder/userfiles/files/430339975.pdfIn PDF document text
    • http://tlumacz-bialystok.pl/pliki/file/givobosupaxaloxi.pdfIn PDF document text
    • https://starfoil-mail.nl/uploads/wysiwyg/60041231911.pdfIn PDF document text
    • http://archiprojektai.lt/app/webroot/uploads/userfiles/files/kubatutipezu.pdfIn PDF document text
    • https://brihat-group.com/assets/userfiles/files/janaporapijojo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=samsung+note+20+teardownPDF 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_off0000d8b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8B0 10956 bytes
SHA-256: d9c28b5ca9822bc8480ac38beae7b855193d4d1dae35234ad6d29b04a01c59e1
font_01_sfnt_off0000f203.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF203 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010a15.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A15 18468 bytes
SHA-256: f65f428c2994be75a57358ffde1f0f25e1379a18daf1626e8b71a52779a5884b