Malicious PDF — malware analysis report

Static analysis result for SHA-256 b84bef2de3fde02d…

MALICIOUS

PDF

85.3 KB Created: 2021-08-07 05:49:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 1db405c38293cee96b6cd365b6a71e40 SHA-1: 7a423192211d17800880c3f3ed428194e370060c SHA-256: b84bef2de3fde02dda7ee150b107137ab2388edd78db198e41b4e4f5adfc5d30
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains a link farm pointing to multiple compromised WordPress sites, which in turn host other PDF files. This suggests a multi-stage redirection scheme likely intended to obscure the ultimate destination and evade detection. The ML classifier and ClamAV detection strongly indicate malicious intent, consistent with phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 https://regalcabs.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160868db4e2cb9---gotadeperegudowobo.pdf In PDF document text
    • http://lookupagency.es/wp-content/plugins/formcraft/file-upload/server/content/files/160fd9af940c29---29917929025.pdfIn PDF document text
    • http://www.asslar.de/downloads/3609079134.pdfIn PDF document text
    • http://prodesign31.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1606d478852112---7179741974.pdfIn PDF document text
    • http://kmbb.at/userfiles/file/52764647164.pdfIn PDF document text
    • https://master.plus/wp-content/plugins/super-forms/uploads/php/files/79db6f62bdbcef30b7f93e7c6d0db97d/22567093324.pdfIn PDF document text
    • http://carrollcountylawyers.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/roxebexuzaxunenudotedoge.pdfIn PDF document text
    • https://dm288.rs/slicice/file/95870552472.pdfIn PDF document text
    • https://www.ezhealthcheck.com/wp-content/plugins/super-forms/uploads/php/files/tkhmlvd0mopv1houim9jkfnfop/96983856527.pdfIn PDF document text
    • http://ontsgoi.shop/uploads/files/titadelasobodufoforoj.pdfIn PDF document text
    • http://angarakshaksecurity.com/userfiles/file/joxidawazakir.pdfIn PDF document text
    • http://secretinvitation.net/images/files/muraloxu.pdfIn PDF document text
    • https://adium.ru/userfiles/file/fetedapif.pdfIn PDF document text
    • http://kondicionery-lubertsy.ru/upload_picture/file/pizizivikinepexot.pdfIn PDF document text
    • https://lightingsystemscol.com/wp-content/plugins/super-forms/uploads/php/files/462290be65d91a770957804d81f65d7c/zuzeduluxogoxaxazekijela.pdfIn PDF document text
    • https://retrofitoman.com/ckfinder/userfiles/files/10956351576.pdfIn PDF document text
    • https://carpanea.it/wp-content/plugins/super-forms/uploads/php/files/d0ae2926ea1c2468e96a590cd3401701/80921593688.pdfIn PDF document text
    • https://monarchwinemerchants.com/wp-content/plugins/super-forms/uploads/php/files/6a714a699502731e4e0fbff043c2b542/nowufejez.pdfIn PDF document text
    • https://alshaabcoop.com/userfiles/file/nuxajatozajutowakudanik.pdfIn PDF document text
    • https://evg-prague.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160ab27bc5bb3d---32253867161.pdfIn PDF document text
    • https://www.numberoneporthill.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160c898728371d---64541135234.pdfIn PDF document text
    • http://asea-admin.com/_userfiles/file/20210611095432.pdfIn PDF document text
    • http://labcoop-jsc.com/wp-content/plugins/super-forms/uploads/php/files/9ekhsot42crelt60rvra6s7e2u/gawekepilebefunagijazoran.pdfIn PDF document text
    • http://www.johnknox.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1609105c91ec53---jurajuba.pdfIn PDF document text
    • https://www.gml.de/wp-content/plugins/formcraft/file-upload/server/content/files/16073875cc5064---3933225789.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=homojen+kar%C4%B1%C5%9F%C4%B1mlara+%C3%B6rnek+verPDF 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_off0000e766.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE766 10692 bytes
SHA-256: 3ab0d7a35301678ee6aa7fa6b5f077acf93167229447e4011227bddf079e4a8a
font_01_sfnt_off0000ff6b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF6B 18664 bytes
SHA-256: 0e338c11091b9b431c6153bbed85d475a0bd04aec1b6eafedb88f29b3cc8107e
font_02_sfnt_off00012ce8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12CE8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1