Malicious PDF — malware analysis report

Static analysis result for SHA-256 bfce34b8cd90577d…

MALICIOUS

PDF

79.7 KB Created: 2021-09-13 02:13:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: fa67eaf9dec01959b25fb06b255a6c09 SHA-1: 9329f2213d36f6cecedd78db8d27b599f7129aac SHA-256: bfce34b8cd90577df9a9cc3ec2dfab658a6a8770535c50c0e1ecdc52a66f87e6
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file contains numerous embedded URLs that point to other PDF files hosted on compromised websites, a technique often used for SEO manipulation or to distribute further malicious content. The ML classifier strongly indicated maliciousness, and the heuristics identified it as a link farm on disposable hosting, suggesting a malicious intent to redirect users. No scripts were extracted, limiting the analysis of direct execution capabilities.

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://phoenixknights.co.uk/wp-content/plugins/super-forms/uploads/php/files/5a7936eb7dfbed5fdc7e7ec005233af2/96263626456.pdf In PDF document text
    • https://travelinnsuites.com/nbloom/fckuploads/file/melebaxalizetezobov.pdfIn PDF document text
    • http://jenan.com/ckfinder/userfiles/files/terosogabazerutufome.pdfIn PDF document text
    • https://odontologosmalca.com/images/userfiles/file/85414186534.pdfIn PDF document text
    • http://fashioneducation.ru/userfiles/file/27178876169.pdfIn PDF document text
    • http://thebankcardservice.com/uploads/files/55144043680.pdfIn PDF document text
    • https://regiefranchet.fr/userfiles/files/zaniwekopajawinala.pdfIn PDF document text
    • http://builderall.info/userfiles/file/gogovosodugosemedas.pdfIn PDF document text
    • http://hjhchem.com/upload/files/xoxulewusej.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613aa28daab59---jeralimaxedip.pdfIn PDF document text
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/v6ki54ev598cg163p3skhjrkh4/76719000133.pdfIn PDF document text
    • http://www.gunyagder.org.tr/wp-content/plugins/super-forms/uploads/php/files/k90jptl583gkt6qkhso9ib7lj7/xonolegevamikuvubi.pdfIn PDF document text
    • http://seamacros.com/upload/file/korawalakukexobez.pdfIn PDF document text
    • http://hanilkwanla.com/uploads/files/91523419368.pdfIn PDF document text
    • https://gruppopolidori.com/upload/image/file/21455990990.pdfIn PDF document text
    • http://khyljg.com/uploadfiles/files/77269638771.pdfIn PDF document text
    • http://solis.altrodesign.eu/ckfinder/userfiles/files/77476183081.pdfIn PDF document text
    • https://lixtech.com.tw/ckfinder/ckfiles/files/95840132316.pdfIn PDF document text
    • https://abctranslink.com/ckfinder/userfiles/files/zuxuroviditir.pdfIn PDF document text
    • http://ventexevent.se/uploads/file/taliwidudavatud.pdfIn PDF document text
    • https://petrovsky14.ru/docs/files/42429391340.pdfIn PDF document text
    • http://ei-windykacja.pl/upload/file/rowipevujonupom.pdfIn PDF document text
    • http://basyapiemlak.com/yukleme_klasoru/userfiles/file/wafagi.pdfIn PDF document text
    • http://centralcogtc.com/uploads/file/33949221306.pdfIn PDF document text
    • https://mertlakustika.cz/images/pages/file/10474263139.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=seo+tool+keyword+rankingPDF 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_off0000d389.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD389 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000eb9b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB9B 17328 bytes
SHA-256: 7cb4f7ad8f560dc182d9919d3f92f58f861a2638d3c9e3f313a2380ca7863469
font_02_sfnt_off0001188d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1188D 10624 bytes
SHA-256: 488edd7fc168bdda0e062f1489a10e6732fb8c667934b3839d9c5d02481e729c