Malicious PDF — malware analysis report

Static analysis result for SHA-256 fa4ca7902a4aad47…

MALICIOUS

PDF

80.6 KB Created: 2021-09-16 16:10:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: f8283de7e488cedf179abe735a268ed1 SHA-1: 0dcb44c3c920f4e92b1bfc774f22e4a92a895f77 SHA-256: fa4ca7902a4aad4793c09a0f253f8e9a0e38b7a05e580a6da076c41f249750b6
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file contains a large number of embedded URLs, many of which point to PDF files hosted on various domains. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates that this is a link farm on disposable hosting, suggesting a malicious intent to distribute further content. The ML classifier also strongly flagged this PDF as malicious.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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://limpiasol.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c63198cfdc---42829566839.pdf In PDF document text
    • https://wanna-drive.nl/files/File/18945503038.pdfIn PDF document text
    • http://karaokejdi.com/ckfinder/core/connector/php/upload/files/kixibumudiputezijege.pdfIn PDF document text
    • http://lamelove-zakryti.cz/userfiles/file/2214223314.pdfIn PDF document text
    • http://scuolascifondocortinadolomiti.it/userfiles/files/gubuwekiminefizedi.pdfIn PDF document text
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613b03e6e4588---fegupezunesozeluxutikumit.pdfIn PDF document text
    • https://simondaulte.com/ckfinder/userfiles/files/fibojo.pdfIn PDF document text
    • https://kamwalibais.com/userfiles/file/31181746452.pdfIn PDF document text
    • http://gaudi.tw/upload/files/54138586232.pdfIn PDF document text
    • https://bisleriuber.genefied.co/ckfinder/userfiles/files/37548470313.pdfIn PDF document text
    • https://saigonservices.vn/images/uploads/files/82856681428.pdfIn PDF document text
    • http://tehpromyar.ru/media/file/28179358238.pdfIn PDF document text
    • https://binarbaidtrading.com/public_html/userfiles/file/tediwumutigefefijeveras.pdfIn PDF document text
    • http://mineraux-et-lithotherapie.fr/ckeditor/upload/files/xaturufidozizulebuluxa.pdfIn PDF document text
    • https://ever-progress.com/upload/files/gutesijotifos.pdfIn PDF document text
    • https://limpjet.com.br/wp-content/plugins/super-forms/uploads/php/files/b83c8a40e874909d57733e37d5fd3f80/79053075851.pdfIn PDF document text
    • http://www.yourhealthyourchoice.org/wp-content/plugins/formcraft/file-upload/server/content/files/16140e4ee0ce07---90869976577.pdfIn PDF document text
    • http://madmojo.com/fckupload/file/25676030674.pdfIn PDF document text
    • https://acrgruppe.de/userfiles/file/91862477147.pdfIn PDF document text
    • https://ceadersvalet.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613cd0fcb43aa---37891710828.pdfIn PDF document text
    • https://dsverano.com/UserFiles/File/xegulemojamimudesazenar.pdfIn PDF document text
    • https://ofly.om-digitalsolutions.cn/upload/files/kuxoxe.pdfIn PDF document text
    • http://nriloan.jctoursandtravels.in/files/gugamolifofotexazositu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=lehninger+8th+edition+pdfPDF 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_off0000d993.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD993 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f1a5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1A5 16944 bytes
SHA-256: b00c71cb221b63edda6a4044eb89c69ed75c2d80d08358625be77c876d60f88f
font_02_sfnt_off00011d5a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D5A 10564 bytes
SHA-256: 2f673e4787ca0fb1233ec8143bd3fae2d487dd3ad062b6fb03c90a76e9c4c436