Malicious PDF — malware analysis report

Static analysis result for SHA-256 b37b878135de08ae…

MALICIOUS

PDF

86.5 KB Created: 2021-09-08 03:52:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 6b53c4fd4fbe14e0a893ad4c10bf3dae SHA-1: 9fb6a8c8d901e67e6181c8203b2b65495d49a1cb SHA-256: b37b878135de08aec895cbc74b4972bc9d967d240ae72d1f280a35987bae2152
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many pointing to compromised WordPress sites, suggesting a link farm designed to redirect users to potentially malicious content. The presence of these links and the overall structure indicate an attempt to leverage SEO or host malicious redirects.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://weblative.com/wp-content/plugins/super-forms/uploads/php/files/3vlbgfrfd92dnrm7u5rhm0f2p3/puwexo.pdf In PDF document text
    • https://tcufroghouses.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608fe02b941f0---86039002593.pdfIn PDF document text
    • http://mextro.de/upload/files/75687509868.pdfIn PDF document text
    • http://suncitygroup.ir/basefile/suncitygroupir/files/38518050592.pdfIn PDF document text
    • http://wheatland1971.com/clients/25033/File/gesafinize.pdfIn PDF document text
    • https://mauspro.net/upload/files/tevotise.pdfIn PDF document text
    • https://www.novet.de/wp-content/plugins/formcraft/file-upload/server/content/files/160ac7ba75106b---nanunofamodu.pdfIn PDF document text
    • http://thegroverestaurantnj.com/userfiles/files/bawororeseje.pdfIn PDF document text
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/75527b46aad0dfbe0749db076fe06e1d/78889309056.pdfIn PDF document text
    • https://dmvassociates.com/wp-content/plugins/super-forms/uploads/php/files/5139ab9980a2f5018fea876edb01fc2d/bamogasogusadojem.pdfIn PDF document text
    • http://rallyteamwalraven.nl/file/86246661979.pdfIn PDF document text
    • https://flexrocksrollovers.com/wp-content/plugins/super-forms/uploads/php/files/n9gtj0lsd0a98fk2rbhp1hde8n/83018529663.pdfIn PDF document text
    • http://dobryremont.pl/ebobas/portal/app/webroot/img/tmp/file/16205491274413.pdfIn PDF document text
    • http://philippinesroadshow.com/wp-content/plugins/super-forms/uploads/php/files/b1822a0d0ec3cdf4fb956963beff6a49/95431497681.pdfIn PDF document text
    • https://tkpmission.org/wp-content/plugins/formcraft/file-upload/server/content/files/160961fc677a28---simagazeludor.pdfIn PDF document text
    • https://elnativocoffee.com/silver/upload/files/79188226773.pdfIn PDF document text
    • http://ropesadventure.com/d/files/46691123020.pdfIn PDF document text
    • http://zawayakw.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aa8aa541754---pazigafasugubama.pdfIn PDF document text
    • https://www.superioreagle.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076260b39d4a---rozurinukel.pdfIn PDF document text
    • https://eminenceconstruction.ca/viking1/uploads/files/46713648925.pdfIn PDF document text
    • http://jucal.es/images/file/41544893.pdfIn PDF document text
    • https://tramtron.vn/uploads/files/files/fuvawupomeg.pdfIn PDF document text
    • https://sunridgecorp.com/uploads//files/202108070146105568.pdfIn PDF document text
    • http://www.playerclub.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160abc0905b71a---gajajamamakesojegezad.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=cara+convert+file+jpg+ke+pdf+offlinePDF 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_off0000ec51.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC51 10944 bytes
SHA-256: 74ac2935301a49abf2b2d84f6b378caee60b24922516888c70716662f43ffa1f
font_01_sfnt_off00010595.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10595 17888 bytes
SHA-256: 1c76e278e347b78cabd01c93c076b911de6964f4915cfa0492611bc71e551646
font_02_sfnt_off00013406.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13406 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1