Malicious PDF — malware analysis report

Static analysis result for SHA-256 b16a875826871126…

MALICIOUS

PDF

140.7 KB Created: 2021-07-22 06:07:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: d351affac0fcf690c3684a3f4f225daa SHA-1: 0ad8cd76065d100d2f71cce482a553c458551e79 SHA-256: b16a875826871126e2d30bf5429163f829d23e95b28f2de501f06a978a69d232
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to compromised WordPress upload directories, indicating a link farm designed to host malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent. The document body was unreadable, but the heuristics indicate a phishing or malware distribution lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9922

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://www.rockandroll.blog.br/wp-content/plugins/super-forms/uploads/php/files/qtbki61uc78623sf64imcmjkjo/lutepojowekoxiluteku.pdf In PDF document text
    • https://neavocats.com/wp-content/plugins/super-forms/uploads/php/files/0eb8d8c9f717f05594f5b1813cb29806/54534412798.pdfIn PDF document text
    • http://ednak.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094793fc8c17---60459756717.pdfIn PDF document text
    • https://kvkumariajnkvv.org/singhania/downloads/file/titaridorimepesenuzem.pdfIn PDF document text
    • http://stellamaris.cz/userfiles/fefij.pdfIn PDF document text
    • https://www.sadcmedia.com/wp-content/plugins/super-forms/uploads/php/files/otc63m32kklv2kkjrsuq8tc66e/vobiniriv.pdfIn PDF document text
    • https://abugfreemind.com/userfiles/file/judizijemekopalusekare.pdfIn PDF document text
    • https://creationstationdance.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b2368254f65---xuvelir.pdfIn PDF document text
    • http://www.hypnotiseur.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f664bd0316---22542288932.pdfIn PDF document text
    • http://www.birapart.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c7436c1dbfc---31278788806.pdfIn PDF document text
    • http://wasserentkalkung.at/ckfinder/userfiles/files/28473260898.pdfIn PDF document text
    • http://hifitness.hu/userfiles/file/powomisanurozupipudanibi.pdfIn PDF document text
    • http://podiummoda.ru/userfiles/file/jovidajibigogolelexabu.pdfIn PDF document text
    • https://noddy.nu/images/file/84882099156.pdfIn PDF document text
    • http://pansophers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bc9410612cc---13370747211.pdfIn PDF document text
    • http://birons.net/wp-content/plugins/super-forms/uploads/php/files/acdf8ae5511b58dde59441c803832c9b/finawanibojesijedabupin.pdfIn PDF document text
    • https://kodeac.com/wp-content/plugins/super-forms/uploads/php/files/m5c536ikorhlcnu0hgk51he1v1/bixedirekewe.pdfIn PDF document text
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/q7dchq8bv2gcm52rjfbkqkqnvl/megegubivapufekebitub.pdfIn PDF document text
    • http://mobydick-band.de/fckdata/file/13618395935.pdfIn PDF document text
    • https://drvishweshwari.in/userfiles/file/38163345435.pdfIn PDF document text
    • https://robinio.de/wp-content/plugins/super-forms/uploads/php/files/2ktr21anvnibo0ri7t541ffedn/98310321123.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e959047f474---12225956502.pdfIn PDF document text
    • http://www.hypnotiseur.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081dd61c7f66---kalujoluxojekepejede.pdfIn PDF document text
    • http://lucann.com/Upload/file/maxugopisefelixux.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=on+the+role+of+knowledge+graphs+in+explainable+aiPDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001a4bc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1A4BC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001bcce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1BCCE 22104 bytes
SHA-256: c41b60df8726b9acab7a56632cf64d57bb4f541f5ca2a7c7b9b7035e45a8b4c2
font_02_sfnt_off0001f19b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1F19B 16676 bytes
SHA-256: 8e53d0df7606de16e0980d4e97148545ad0a548d345c5a44f5d3f0aac34c0939
font_03_sfnt_off00020948.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x20948 11220 bytes
SHA-256: b91d57740cdffcc71a5b9673ae58f98d6a024d8c4b4b0a23175f59eb517ebe61