Malicious PDF — malware analysis report

Static analysis result for SHA-256 56c1badd4ba2d895…

MALICIOUS

PDF

77.9 KB Created: 2021-09-01 05:26:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 9adff57847947552e37ecba90a0812ad SHA-1: c4a9f9f09232967038f6233e78a18ff2844d532a SHA-256: 56c1badd4ba2d895178854f07e55a4c4064ed1df1d987e5957cdcd8b9bc8d15f
156 Risk Score

Malware Insights

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

The PDF file contains a large number of embedded URLs pointing to compromised WordPress upload directories and other disposable hosting. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or malware distribution. The file's structure as a link farm suggests it's designed to redirect users to malicious content hosted on these compromised sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9989

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://mas.vacations/wp-content/plugins/formcraft/file-upload/server/content/files/16088e279f3eed---perexanori.pdf
    • https://gresathouse.com/wp-content/plugins/super-forms/uploads/php/files/c059a49a7e6bd87d660e596901d0250b/tujar.pdf
    • http://ettermanenterprises.com/ckfinder/userfiles/files/saziga.pdf
    • https://vickers-electronics.co.uk/wp-content/plugins/super-forms/uploads/php/files/b9a5770b39ffac1cecd8c331cf53f783/29060722.pdf
    • http://malbreil.com/userfiles/file/12523402711.pdf
    • http://ntvietnga.com/upload/files/guvatajumifadelizokor.pdf
    • http://svs-pm.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b4df7f35f1---27785484480.pdf
    • http://www.marcado.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1612e6cffb6ab3---zebirija.pdf
    • http://teormech.ru/teormech/usrimg/file/zavexukivajulup.pdf
    • https://christianboudreau.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b88ed2b36b4---riboxababobotevetika.pdf
    • http://www.supair-lux.hu/ckfinder/userfiles/files/modolo.pdf
    • https://www.hungarianassociation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160fe3c5991978---fiwozugefadovidivejipebik.pdf
    • http://daimarconstrucciones.com/images/admin/file/12024716868.pdf
    • https://tcufroghouses.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aa502db00c8---dolukavijik.pdf
    • http://zigzagontwerp.nl/sites/default/files/file/vigotasofisokozabowi.pdf
    • http://gazosilikatnn.ru/uploads/files/sabiku.pdf
    • http://exmar.it/foto_fck/file/39814254443.pdf
    • https://husvagnsexpo.se/wp-content/plugins/formcraft/file-upload/server/content/files/160ac24dede4e5---18437492621.pdf
    • https://novahealthclinic.ca/userfiles/file/juzexuketere.pdf
    • http://aliceinformaticasrl.com/user/pages/gukize.pdf
    • http://middlegeorgiacoinclub.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075d49f2100e---43162933869.pdf
    • http://rasciindia.com/firetech/ckupload/files/giwerupuvipirenideji.pdf
    • https://ketgate.eu/wp-content/plugins/super-forms/uploads/php/files/d734a70945a623746f0dceec09d3a314/batodojemutigul.pdf
    • http://www.wcd.com.tw/ezadmin/ckfinder/userfiles/files/79383495470.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=hourly+gainers+bse
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ce99.bin
b2837da04e1f9b2f27a2ad33ad744e9cb2fc6a3cec13072d9934e394496990d1
pdf-font-stream PDF embedded font (sfnt) at offset 0xCE99 16640 bytes
font_01_sfnt_off0000f9b0.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF9B0 16792 bytes
font_02_sfnt_off000111c7.bin
71177f85067cb29104323b2db17cd364daa9bf1333210980ecd8318edb645f2a
pdf-font-stream PDF embedded font (sfnt) at offset 0x111C7 10528 bytes