Malicious PDF — malware analysis report

Static analysis result for SHA-256 8a64e32fd665ec4d…

MALICIOUS

PDF

78.2 KB Created: 2021-08-14 20:48:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 4a7ecd94a0146916c908e84a5b64db50 SHA-1: 6286ac41d7582841491e76152b134b0a81e508a3 SHA-256: 8a64e32fd665ec4d1f6957e85c6f1dfd9ba06127518de74e9b61e9b1e61f334d
96 Risk Score

Malware Insights

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

The PDF contains a large number of embedded URLs, many of which point to compromised WordPress sites. The ML classifier strongly indicated maliciousness, and the PDF structure suggests it's designed to lead users to external, potentially harmful, content. No scripts were extracted, limiting the analysis of direct execution vectors.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

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://wasserburg.pl/userfiles/file/fimepovazakobijedekujisuj.pdf In PDF document text
    • http://intechsol.kz/wp-content/plugins/formcraft/file-upload/server/content/files/160c3fa2b4e6a7---63037156287.pdfIn PDF document text
    • http://ildongwire.com/userfiles/file/libolero.pdfIn PDF document text
    • http://ntep2008.com/UserFiles/File/48549309577.pdfIn PDF document text
    • https://readxyz.org/wp-content/plugins/super-forms/uploads/php/files/831ef47b6bcee969737743fabfcd5ec3/matubowozuwatelixobinipu.pdfIn PDF document text
    • http://ontheedgeofnow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ed6346fd3d---zojuxogumupedefudamadetej.pdfIn PDF document text
    • https://www.conkite.com/wp-content/plugins/super-forms/uploads/php/files/fefbc2b4c0abddb1f543c4d9873bbb29/73241104082.pdfIn PDF document text
    • http://www.brennholz-heinlein.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b843511afa8---17971204994.pdfIn PDF document text
    • http://kag.fr/userfiles/file/medexubivazilaku.pdfIn PDF document text
    • https://tresonance.org/uploadfiles/nutegivodu.pdfIn PDF document text
    • http://wwstationery.com/files/file/17884846681.pdfIn PDF document text
    • http://vmkmsz.hu/userfiles/file/62759748412.pdfIn PDF document text
    • http://amwordpress.org/wp-content/plugins/formcraft/file-upload/server/content/files/160b5be6054cf5---43568285651.pdfIn PDF document text
    • https://www.ayersworthglen.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e455c6dcd22---10577075496.pdfIn PDF document text
    • http://aggengr.com/uploads/CMS/file/votibibili.pdfIn PDF document text
    • http://profisystem.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160c57be1efb84---2368800826.pdfIn PDF document text
    • http://www.optionassurance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1607fcdfba2f39---88276011428.pdfIn PDF document text
    • http://abpaluso.com/upload/file/geguwasilobawizura.pdfIn PDF document text
    • https://action-roofing.com/wp-content/plugins/super-forms/uploads/php/files/e5207a268bd801296aa483b346058e44/46473374434.pdfIn PDF document text
    • http://auldskoolrocks.com/clients/878384/File/dixewixuwim.pdfIn PDF document text
    • http://asijskepotraviny.cz/files/file/botavudiletilipede.pdfIn PDF document text
    • https://neavocats.com/wp-content/plugins/super-forms/uploads/php/files/e684cd85946977c180f9e1cc6a29b63f/nuviwegur.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=star+warfare+mod+apk+android+1PDF 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_off0000cc88.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC88 17268 bytes
SHA-256: 0fff3d55d44bd9c13dafa510e1d3f5f52826f816c8946d2c36abf65cc8de3c6e
font_01_sfnt_off0000f9cd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9CD 10748 bytes
SHA-256: dadd89ebee22382c91136910d8d91c49fb818b6c98ed1d4a445977c517359290
font_02_sfnt_off000112a1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x112A1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1