Malicious PDF — malware analysis report

Static analysis result for SHA-256 9158f8b8770d04ed…

MALICIOUS

PDF

91.0 KB Created: 2021-08-10 12:18:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 01819ee9e37fda335fd84338455c7ac8 SHA-1: 76eab5cd41f6e9214f8d62ba1c95f1eeebd6adad SHA-256: 9158f8b8770d04ed86f5261f09edc546217e970b44c516de08ed44dabc323881
96 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites acting as link farms. The ML classifier strongly indicated maliciousness, and the structure suggests an attempt to distribute traffic or potentially host further malicious content. No scripts were extracted, limiting the analysis of direct execution vectors.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9913

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://www.hcibatiment.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16088dccf6de88---bugukibufebeture.pdf In PDF document text
    • http://rrbrentacars.com/files/others/fizafowowewumunemozex.pdfIn PDF document text
    • https://christianboudreau.com/wp-content/plugins/formcraft/file-upload/server/content/files/160743acac74ba---96434183650.pdfIn PDF document text
    • https://rjiminfra.com/wp-content/plugins/super-forms/uploads/php/files/058c4ac430c71c6b98ea9e3138607a8f/lomaxujurid.pdfIn PDF document text
    • https://www.ikedatosou.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f98300bd4f---zaderugivugazirogused.pdfIn PDF document text
    • http://sarlampa.ru/upload_picture/sovifuzemupaxikusutip.pdfIn PDF document text
    • http://alsumiri.net/wp-content/plugins/super-forms/uploads/php/files/31d72818cdfa649d6a8650afafa3d7b5/36157112992.pdfIn PDF document text
    • https://alakharia.com/public_html/userfiles/file/2261149499.pdfIn PDF document text
    • http://historia-bfured.hu/userfiles/file/31583256863.pdfIn PDF document text
    • https://liniagdanskzydowo.pl/files/13665772863.pdfIn PDF document text
    • http://www.annaleehuber.com/content_files/file/jumepavuxozatedika.pdfIn PDF document text
    • https://trucraftsmanship.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f27242b5492---gejojonajiperar.pdfIn PDF document text
    • http://aldo-ins.com/userfiles/file/guxefibegumofev.pdfIn PDF document text
    • https://feniks9.ru/ckfinder/userfiles/files/nudotubilunovo.pdfIn PDF document text
    • http://www.deco-interieure.com/userfiles/file/46147392996.pdfIn PDF document text
    • https://www.northamericatalk.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082b41d74b16---48958142231.pdfIn PDF document text
    • https://swimproject.eu/wp-content/plugins/super-forms/uploads/php/files/529337cfb3eef5d7efcdeaa8a18c5cb1/93614211854.pdfIn PDF document text
    • https://rffsev.ru/wp-content/plugins/super-forms/uploads/php/files/272e1de3a5ab5adacf08ee3e8e667e1c/vadiwugagomagipojeminoxin.pdfIn PDF document text
    • http://cpgny.com/userfiles/files/fatefuboxofazipepivufu.pdfIn PDF document text
    • http://architettotoma.it/userfiles/files/36665520608.pdfIn PDF document text
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/p6ko8j9g24a5939nfo0a3s4ic7/55415591295.pdfIn PDF document text
    • https://www.basur-tedavisi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160759613898ee---15589575797.pdfIn PDF document text
    • http://springswellness.net/wp-content/plugins/formcraft/file-upload/server/content/files/160ee5d5461fad---dozapotaza.pdfIn PDF document text
    • http://ahcxdq.com/uploads/file/261213287003.pdfIn PDF document text
    • https://414movement.com/wp-content/plugins/super-forms/uploads/php/files/944672b3b1518b35689e3e5907473ca8/11298755705.pdfIn PDF document text
    • https://t4g.nasscomfoundation.org/wp-content/plugins/super-forms/uploads/php/files/mh26k3h7lt675iqm53720h3ds1/88092633313.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=guitar+tuna+pro+apk+latest+versionPDF 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_off0000f5e2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5E2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010df9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10DF9 10544 bytes
SHA-256: a5ef1106e1901996517f11e550a9837421f9216cf5b8c85ff0e06b35d52974f0
font_02_sfnt_off00012627.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12627 21964 bytes
SHA-256: 4e33dcc2a8f9b59d567f2ac5f57457baf6b99a338dca0cff7ff494a0f161b372