Malicious PDF — malware analysis report

Static analysis result for SHA-256 7666a564ad283778…

MALICIOUS

PDF

79.5 KB Created: 2021-06-28 17:24:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: c65c8c3b8b47be0e44d8cad9fccd42b1 SHA-1: 095dcf762c0b49eb916c15ca45d437f583602941 SHA-256: 7666a564ad283778791b6a3a1019c2db9521f1c9ae52cfd7b0c46ccce9d69272
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document was flagged by an ML classifier as malicious. It contains numerous embedded URLs that form a link farm, pointing to other PDF files hosted on various domains, some of which appear to be compromised CMS uploads. The primary function seems to be redirecting users through a chain of links, potentially for SEO manipulation or to obscure the final malicious destination.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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 http://tlxzkj.com/uploads/file/261954225049.pdf In PDF document text
    • http://pizzeria-millemiglia.de/app/webroot/img/editor/file/furoxinugonivapuvo.pdfIn PDF document text
    • http://lucann.com/Upload/file/62250750238.pdfIn PDF document text
    • http://newabel.com/ckfinder/userfiles/files/pafugesisesuraxaniw.pdfIn PDF document text
    • https://www.straightmyteeth.eu/wp-content/plugins/super-forms/uploads/php/files/dd12057414e02817129979db5ffcf107/soruxizelofut.pdfIn PDF document text
    • http://izdepskifamily.com/clients/1/1a/1adacdf247316bc4617b3617d965acc7/File/73427275774.pdfIn PDF document text
    • https://esteticarcare.com/wp-content/plugins/super-forms/uploads/php/files/82d9241847edb1f6139ae2618f139a56/mipagavujikuxolidasu.pdfIn PDF document text
    • http://ipvoicenj.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608b50a37994b---8550978845.pdfIn PDF document text
    • http://www.drop-lok.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a656f4dc363---83458265153.pdfIn PDF document text
    • https://nailseasupportgroup.com/wp-content/plugins/super-forms/uploads/php/files/ed89cf45ca73a0d147fe1d78b86e8d9a/24686270175.pdfIn PDF document text
    • http://mouaumfb.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607effda0a6cf---bokegido.pdfIn PDF document text
    • http://global-insurance-broker.de/downloads/zegibexuxazunesirumiva.pdfIn PDF document text
    • https://smarttactic.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160b8652376732---sozozunitukitefoniz.pdfIn PDF document text
    • http://luberoff.com/userfiles/file/54153882816.pdfIn PDF document text
    • http://lavera.it/wp-content/plugins/formcraft/file-upload/server/content/files/160774c9c04f10---41883811748.pdfIn PDF document text
    • http://msinziniering.com/userfiles/file/50752347585.pdfIn PDF document text
    • http://hyunbulsa.org/~ewedd2/userfiles/file/darokukepipab.pdfIn PDF document text
    • https://www.colegiodesafio.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/1608c561712254---20854778943.pdfIn PDF document text
    • http://evohome.pl/userfiles/file/35235503151.pdfIn PDF document text
    • https://holzhaus-suedtirol.it/wp-content/plugins/formcraft/file-upload/server/content/files/1608e1d78776ce---43125155014.pdfIn PDF document text
    • https://amirep.com/wp-content/plugins/super-forms/uploads/php/files/b7cf14a28e6542f5efcf893560e962fb/9043364711.pdfIn PDF document text
    • https://ngoctraithaibinhduong.com/uploads/news_file/tugusukejedefowolakovowex.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=nts+old+paperPDF 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_off0000d5a8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5A8 17156 bytes
SHA-256: c5b2fbf2ddcafe09d4ef3b088a0ac103c82ecf9bdfe3f4bd260657850da28878
font_01_sfnt_off00010275.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10275 10168 bytes
SHA-256: 7e053f2503e94a2abd660c16cef6dd24e79e1f5291bb073a4371918d55eeeea0
font_02_sfnt_off00011962.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11962 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1