Malicious PDF — malware analysis report

Static analysis result for SHA-256 ca7289ce01003ea4…

MALICIOUS

PDF

95.8 KB Created: 2021-09-07 13:33:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 47fd5d7d27d5c2a7e97177879509a3da SHA-1: b5bd268855a405c3a1b11151e303cee458e622b5 SHA-256: ca7289ce01003ea4d5cfd8c1c7bc258e585914e3b8310e1f5dc528f22558f95e
156 Risk Score

Malware Insights

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

The PDF was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm pointing to numerous compromised websites, suggesting a phishing or malware distribution campaign. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, providing no direct user-facing content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9936

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://knowleangling.co.uk/ckfinder/userfiles/files/78541948664.pdf In PDF document text
    • http://southportrubbish.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e0ed7f7996c---69875720187.pdfIn PDF document text
    • http://woodbridgeabw.com/uploads/files/vekataganak.pdfIn PDF document text
    • https://nhaban24h.com.vn/wp-content/plugins/super-forms/uploads/php/files/q3m8f72rchfn9ivn3kp7f7bkn5/38832970084.pdfIn PDF document text
    • https://kund-in.com/userfiles/file/44072983405.pdfIn PDF document text
    • https://www.parkgest.ch/wp-content/plugins/formcraft/file-upload/server/content/files/16071a0b547bd7---jaxefilulifeku.pdfIn PDF document text
    • http://studioarchperissinotto.eu/userfiles/files/86818685775.pdfIn PDF document text
    • https://www.temsilcifirsatlari.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f4d993e97d---mejujunolutes.pdfIn PDF document text
    • http://carzip.biz/files/uploads/files/13133457870.pdfIn PDF document text
    • http://isisthailand.org/file_media/file_image/file/xekuwivaf.pdfIn PDF document text
    • http://kasargod.net/uploads/file/8517322634.pdfIn PDF document text
    • https://aptitudeclass.com/ckfinder/userfiles/files/gawupot.pdfIn PDF document text
    • http://jkbprivateiti.com/userfiles/file/92292781956.pdfIn PDF document text
    • https://www.sacproblemleri.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e01b21a08e---36298514079.pdfIn PDF document text
    • https://www.dyna-tech.nl/wp-content/plugins/formcraft/file-upload/server/content/files/161207c1a0788c---9696312905.pdfIn PDF document text
    • http://szyqjsj.com/UploadFile/file/20210809204404136.pdfIn PDF document text
    • http://myslizdrave.com/soubory/kamobul.pdfIn PDF document text
    • https://rhuyscampingcar.fr/images/files/totegisi.pdfIn PDF document text
    • http://szyoujin.com/UploadFile/file/20210828175508220.pdfIn PDF document text
    • https://www.birdandwildlifeteam.com/wp-content/plugins/formcraft/file-upload/server/content/files/1611d80762a720---xedewiruzuxavatipukidowux.pdfIn PDF document text
    • https://www.tctnanotech.com/wp-content/plugins/super-forms/uploads/php/files/97728c74fcbf28b2e7b8d622d59b1b0b/kasozukivubaw.pdfIn PDF document text
    • http://baharemadinah.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d20c30637dd---6187995757.pdfIn PDF document text
    • http://simonkuehner.de/gfx/userfiles/files/sojaxesimokegusiwuguz.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160e05bd923b13---febolirezanujabaroxaxu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=para+jumble+questions+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_off00010d99.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D99 20204 bytes
SHA-256: 52a7c8481396c929c9ea5f7bd2b3110e8d7d79742ab7d3e9ef68cb7ad14bd805
font_01_sfnt_off00014050.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14050 11176 bytes
SHA-256: 81e0147d64f50ba7e411a1aab740436f94375b7482be0d91123c923642866914
font_02_sfnt_off000159f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x159F9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1