Malicious PDF — malware analysis report

Static analysis result for SHA-256 15c4c8707376ae74…

MALICIOUS

PDF

79.0 KB Created: 2021-07-22 18:57:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 4ea60a23b8be2441bdea11b0f6ca8018 SHA-1: a13f329ea345adaa4442b9d8d521d573f1b4474a SHA-256: 15c4c8707376ae7455d9360e4a3d44d017e9f228394a350f54b263d232a7b41d
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ML classifiers and ClamAV. It functions as a link farm, containing numerous embedded URLs that point to compromised WordPress upload directories and other potentially malicious sites. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of using disposable hosting for these links, suggesting an attempt to obscure the true destination or evade detection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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 http://broadmoor79.com/clients/864886/File/86604431615.pdf In PDF document text
    • https://regeneracion-capilar.com/wp-content/plugins/super-forms/uploads/php/files/7a98778e8209dee7354dd93fa0063156/1860874152.pdfIn PDF document text
    • https://taiwancy.com/app/webroot/userfiles/files/lewuseduwul.pdfIn PDF document text
    • https://marcuspietrek.de/MARCUS/files/file/sowelokutigetiwudumajaned.pdfIn PDF document text
    • http://cnex.cc/images/blog//file/tudolekusenudavufedaju.pdfIn PDF document text
    • http://poltinik.ru/userfiles/file/70278049556.pdfIn PDF document text
    • http://praconsulgroup.ru/pict/file/difixawafojetonalurejex.pdfIn PDF document text
    • http://aprendanow.com/wp-content/plugins/super-forms/uploads/php/files/981290f99b706e6cb5aebb99de3586aa/97298104640.pdfIn PDF document text
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/7b6b920e1a36efc614859c7b07b80b00/77055498566.pdfIn PDF document text
    • https://www.energetisch-therapeut-estie.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16083c986526c8---denunigu.pdfIn PDF document text
    • https://vannordenvastgoed.nl/userfiles/file/mufajijobaxememajifewi.pdfIn PDF document text
    • https://akproauto.com/nbloom/fckuploads/file/nawapef.pdfIn PDF document text
    • https://consultingexpert.eu/fckeditor/userfiles/file/banobukabekewekavujupe.pdfIn PDF document text
    • http://maility.pl_adresuserfiles/file/wolozoravesuxaz.pdfIn PDF document text
    • https://honda-otolongan.com/upload/files/sujozigijuwogafizune.pdfIn PDF document text
    • http://cgt-fo-csc.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160b0c3e0abba2---8993745430.pdfIn PDF document text
    • http://www.airportlimofortlauderdale.net/wp-content/plugins/formcraft/file-upload/server/content/files/1608e91af2496e---kogitomedumawigudivegav.pdfIn PDF document text
    • http://auksozvynas.lt/userfiles/file/xufizatamefovopuxitutaxi.pdfIn PDF document text
    • https://www.actionconstructionjax.com/wp-content/plugins/super-forms/uploads/php/files/8ef8b33a6884d9b3891b8b53a94a102c/61905336350.pdfIn PDF document text
    • https://www.truesdalepainting.com/wp-content/plugins/formcraft/file-upload/server/content/files/160780360d4393---67222470739.pdfIn PDF document text
    • http://kuehllawpc.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/xemajujokidetup.pdfIn PDF document text
    • http://www.rkcomdesignservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160729dca97f29---4676504027.pdfIn PDF document text
    • http://www.thediethub.in/wp-content/plugins/formcraft/file-upload/server/content/files/160b2148d05a40---zamavoxejuwutup.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=you+in+french+crossword+cluePDF 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_off0000d265.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD265 16960 bytes
SHA-256: 8fcd636b59ea763c69aa1216587cfae1677240870b45a0ccf2a420a81ed566fc
font_01_sfnt_off0000fe56.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE56 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001166d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1166D 10484 bytes
SHA-256: 5b696d06e11af4a1731bc8bd09f017190765beb8dc0a829bd83b3b5f2b179fc4