Malicious PDF — malware analysis report

Static analysis result for SHA-256 ef3beb73ecca2f25…

MALICIOUS

PDF

84.1 KB Created: 2021-09-11 06:01:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-23
MD5: 1cbf516c12192fd74f43dbda4ee0e276 SHA-1: ee19a8ae2f02ceddde8127240c6f917db1eb6134 SHA-256: ef3beb73ecca2f257717ac198adf7168214ee03de29dec348af73c11ce5d96ce
116 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to disposable hosting or compromised CMS upload directories, indicating a link farm designed to redirect users to malicious content. The ML classifier strongly flagged this PDF as malicious, and the presence of multiple external URI heuristics supports this assessment. No scripts were extracted, but the document's structure and URL distribution suggest a phishing or malware distribution lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

Heuristics 6

  • 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.
  • QR-code redirect lure medium SE_QR_LURE
    Document instructs the user to scan a QR code with a phone — consistent with QR phishing, but also common in legitimate documents
  • 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://agriturismolataggiasca.eu/userfiles/files/dituvoduf.pdf In PDF document text
    • https://chaletsuenodesol.de/files/10212864654.pdfIn PDF document text
    • https://relaxationplusmn.com/wp-content/plugins/super-forms/uploads/php/files/220d85910486c7327a6bf3a8817217ce/torobagavijetamosuv.pdfIn PDF document text
    • http://shinex-auto.com/userfiles/file/29425427257.pdfIn PDF document text
    • https://coffeetuanvang.com/Images_upload/files/gakaxodenotomek.pdfIn PDF document text
    • http://hb-hospital.com/file_upload/fck_upfile/file/tadawimo.pdfIn PDF document text
    • http://asfalon.com/__files/file/80897104587.pdfIn PDF document text
    • https://iaido-iaijutsu.ru/userfiles_exc/43755174064.pdfIn PDF document text
    • http://ty-universe.com/image/files/20210902_120559.pdfIn PDF document text
    • http://ipvoicenj.com/wp-content/plugins/formcraft/file-upload/server/content/files/161338334b62d3---3608122791.pdfIn PDF document text
    • http://tainanrup.longi.tw/uploadfiles/files/20210901_211039_2498.pdfIn PDF document text
    • http://karpatskiles.ru/store/file/kemomosujo.pdfIn PDF document text
    • http://sinojjacob.com/userfiles/file/19343560462.pdfIn PDF document text
    • http://autoset66.ru/admin/ckfinder/userfiles/files/nixitaxisovusuz.pdfIn PDF document text
    • http://matsusushionline.com/uploads/files/93797842208.pdfIn PDF document text
    • http://iwilldoit.ru/uploads/files/files/76989586318.pdfIn PDF document text
    • http://akinmedical.com/uploads/file/renovixusositowux.pdfIn PDF document text
    • http://massiimo.com/piceditor/file/16133290999.pdfIn PDF document text
    • https://istanajp.net/contents/files/rixopimuxanefiwewudi.pdfIn PDF document text
    • http://www.sec-ollivier-associes.fr/www/upload/file/mukerakase.pdfIn PDF document text
    • https://centrorevisionimonregalese.it/file/18855212606.pdfIn PDF document text
    • http://peak-experience-japan.com/images/blog/file/25907467794.pdfIn PDF document text
    • https://kolodezrus.ru/wp-content/plugins/super-forms/uploads/php/files/fc9cdaef88158de6744eed4b513f428f/pewiza.pdfIn PDF document text
    • http://wsystem.sk/userfiles/files/52563511064.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=android+12+vs+11PDF 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_off0000e817.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE817 17296 bytes
SHA-256: 079eb1a009aa81284836299f1ed07dda79a4e90504cb1cc9cd83314d769ac39c
font_01_sfnt_off000114cb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x114CB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012ce2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12CE2 10024 bytes
SHA-256: 6e25393626b425fd279bc5633ca364f176f2a7fe72b8214106c67f86f35a907d