Malicious PDF — malware analysis report

Static analysis result for SHA-256 3d8f5e73c1c238b0…

MALICIOUS

PDF

89.7 KB Created: 2021-06-26 11:29:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 12b69161269c58e7e585e83c35c93e66 SHA-1: 903e49260c01bbd36fb519f60ab9d1fe9e98800b SHA-256: 3d8f5e73c1c238b003ba1e905fa847b25e8767b6e17017673f538b5c6d7a10c1
104 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript, a common technique for executing malicious code within documents. Several heuristics indicate the PDF is part of a link farm hosted on compromised WordPress sites, suggesting an attempt to lure users to malicious content. The ML classifier strongly flags this PDF as malicious, supporting the conclusion that it is designed for malicious redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

Heuristics 6

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://avenirpourtous.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1609f6dca3d154---54700425881.pdf In PDF document text
    • http://anhuifan.com/upload_fck/file/2021-5-2/20210502231506575342.pdfIn PDF document text
    • http://bizbecho.com/pa/trainstation/uploads/image/file/90595657615.pdfIn PDF document text
    • http://lalitas-thaimassage-spa.de/wp-content/plugins/formcraft/file-upload/server/content/files/160bbb91a7b326---sotifitiwo.pdfIn PDF document text
    • http://gostium.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a718d0c0f9---86281217380.pdfIn PDF document text
    • http://weberstellen.ch/userfiles/file/24213274835.pdfIn PDF document text
    • http://kennyre.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b47ccc97d58---93651758251.pdfIn PDF document text
    • http://daimarconstrucciones.com/images/admin/file/neposeg.pdfIn PDF document text
    • https://www.ptlittleflower.org/wp-content/plugins/super-forms/uploads/php/files/ju65ilr1ra0qgkba67pe0e3ln6/fazud.pdfIn PDF document text
    • https://wpsqld.com.au/wp-content/plugins/super-forms/uploads/php/files/23cf4325fa7d99f6c074705cd1832200/5894043665.pdfIn PDF document text
    • http://www.training4thefuture.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607e389c721e5---dolulegopa.pdfIn PDF document text
    • http://bergfin.se/wp-content/plugins/formcraft/file-upload/server/content/files/1609bb250736c4---53673715851.pdfIn PDF document text
    • https://imahima.xyz/js/ckfinder/userfiles/files/gitibidogekoxexapedod.pdfIn PDF document text
    • http://outspokenholland.com/userfiles/fckFile/20210620193426.pdfIn PDF document text
    • http://bubblesoflove.net/wp-content/plugins/formcraft/file-upload/server/content/files/1607f87d7ca4e9---xavage.pdfIn PDF document text
    • https://sakitonus.ru/wp-content/plugins/super-forms/uploads/php/files/e2473ed50f6ccf205bdced993693b04f/56126823997.pdfIn PDF document text
    • http://armanetti.com/images/24785665525.pdfIn PDF document text
    • https://www.auditek.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16073cb0ed8312---favonewofodi.pdfIn PDF document text
    • http://unipell.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160774832c04ac---xugopipibefedu.pdfIn PDF document text
    • https://www.davinci.dk/wp-content/plugins/formcraft/file-upload/server/content/files/16075d9d45be2e---8904161754.pdfIn PDF document text
    • https://www.beewellrx.com/wp-content/plugins/super-forms/uploads/php/files/tmp/18608127452.pdfIn PDF document text
    • https://www.sgestrecho.es/wp-content/plugins/formcraft/file-upload/server/content/files/1607ea70be9a39---pesunerevokidusifope.pdfIn PDF document text
    • http://cedresarquitectura.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609497840808b---5780232957.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=causes+of+body+hair+growthPDF 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_off0000fb9b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB9B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000113b2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x113B2 10956 bytes
SHA-256: e48839fe74873a1718329577f757e8ae85eb81c1fd8f01c2e3de8e6f20fdbdd3
font_02_sfnt_off00012d2b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D2B 17028 bytes
SHA-256: be5674a500aa28ba4c8a909501029c30dac469e5f0b136fe706d3b909e452b08