Malicious PDF — malware analysis report

Static analysis result for SHA-256 3bfbffaab80615eb…

MALICIOUS

PDF

85.5 KB Created: 2021-09-17 10:27:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 4e6d2936dbc3297d5f4e71ac48bf8084 SHA-1: 16b31010e878642eeb6f103423233ceff705de2e SHA-256: 3bfbffaab80615eb17603e06a1e42b4b4f6058b5d1383d5bfe58874447f3477a
104 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a significant number of external URIs, many of which point to compromised WordPress sites. These links appear to be part of a link farm designed to redirect users to potentially malicious content. The ML classifier strongly indicates maliciousness, supporting the assessment of a phishing or redirection attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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 https://ketchas.ru/uplcv?utm_term=how+do+i+find+the+owner+of+an+android+phone PDF link annotation
    • http://www.psstrecno.sk/wp-content/plugins/formcraft/file-upload/server/content/files/1613b3490023c3---65121878646.pdfIn PDF document text
    • http://www.advancedevents.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1613c0b36de46b---95555619126.pdfIn PDF document text
    • http://icsbc.ru/fuploader/file/71546488263.pdfIn PDF document text
    • http://entrackintl.com/uploads/wonenibajexezenuxifasi.pdfIn PDF document text
    • http://notarius.jurist-info.ru/uploads/news/fckeditor/file/lawedovopiwejodadij.pdfIn PDF document text
    • http://www.jasfec.com/imgs/uploads/gogukuruwejapelalatanawi.pdfIn PDF document text
    • http://tweedehandswikkelaar.nl/app/webroot/files/userfiles/files/63198833722.pdfIn PDF document text
    • http://www.kzhep.in.ua/wp-content/plugins/super-forms/uploads/php/files/gfqel7ke0i5l4j64o768iimfj0/gazok.pdfIn PDF document text
    • http://sfipl.in/userfiles/file/rafagupo.pdfIn PDF document text
    • https://www.mercedesbenzofaustinservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c493debba7---38304922295.pdfIn PDF document text
    • http://techbico.vn/uploads/image/files/nokebapak.pdfIn PDF document text
    • https://www.taxikladis.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1613239756bf82---35006994595.pdfIn PDF document text
    • https://www.santaterezinha.com.br/js/ckfinder/userfiles/files/54382383149.pdfIn PDF document text
    • http://limobebe.com/userfiles/files/46192053997.pdfIn PDF document text
    • http://crediramasrl.it/public/file/68579657774.pdfIn PDF document text
    • http://www.lukoilmarine.com/ckfinder/userfiles/files/zebuxelejojezefa.pdfIn PDF document text
    • http://mid-europe-ex.com/images/blog/file/42728871951.pdfIn PDF document text
    • http://www.radeton-cz.vasestranky.cz/ckfinder/userfiles/files/xefinebadolimuv.pdfIn PDF document text
    • http://gitishahjahanpur.org/ckfinder/userfiles/files/zarujemikuloletumemokop.pdfIn PDF document text
    • https://urbanlivin.lu/userfiles/files/dagonujedokuraraxeso.pdfIn PDF document text
    • http://profstil.az/userfiles/file/86023002917.pdfIn PDF document text
    • https://thehouseproduction.net/file/85705747613.pdfIn PDF document text
    • http://atsrealtyvietnam.com/upload/files/roxusodumavosejapera.pdfIn PDF document text
    • 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_off0000ea5f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA5F 17620 bytes
SHA-256: fc39407ef13da39d86a413f04ef8db891323051b1313379e2ea9360214601e23
font_01_sfnt_off00011879.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11879 10456 bytes
SHA-256: dd1e44f5c62942a1683e27c1123e32245ce8e6167db5327f36d3ff364edb4c00
font_02_sfnt_off0001301e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1301E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1