Malicious PDF — malware analysis report

Static analysis result for SHA-256 439816f437cef2a9…

MALICIOUS

PDF

91.8 KB Created: 2021-09-01 16:49:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: c90459deaf32a616ee5d340448b563a6 SHA-1: d2520ce57ba51361c4b6d8a7a585850fd8cd89ee SHA-256: 439816f437cef2a98cfe43b9ed6d955d575dd4d75dceac07972c0a4841d9b2c1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, many of which point to potentially compromised WordPress sites and link farms, suggesting a phishing or redirection scheme. The PDF structure and embedded content are consistent with attempts to lure users to external, untrusted resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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.pferde-fuer-unsere-kinder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1611961024fde8---15024959121.pdf In PDF document text
    • https://genesisbehaviorcenter.com/wp-content/plugins/super-forms/uploads/php/files/2d6a384bec4fb09c3c9550dad83fa185/kirirubaxujaxilaveru.pdfIn PDF document text
    • http://bangtaisay.com/uploads/userfiles/file/36560878912.pdfIn PDF document text
    • http://www.sindafaz.com.br/admin/editor/ckfinder/userfiles/files/gamibuzanunefofowamod.pdfIn PDF document text
    • http://sellmysayarah.com/userfiles/files/bojadazijelukigo.pdfIn PDF document text
    • https://lemarko.com/userfiles/file/joxipiwugudenukamaf.pdfIn PDF document text
    • http://446888.top/userfiles/file/9700630485.pdfIn PDF document text
    • https://lakecountyoralsurgery.com/wp-content/plugins/formcraft/file-upload/server/content/files/16095da51c20f2---96830224418.pdfIn PDF document text
    • https://trichynext.com/wp-content/plugins/super-forms/uploads/php/files/7bb1fb4192aa03cf4d23cca1b90cc8fb/59498834168.pdfIn PDF document text
    • https://chowdhurytourism.com/ckfinder/userfiles/files/xupelemiwopobamaxi.pdfIn PDF document text
    • http://fge-service.com/userfiles/file/86528933787.pdfIn PDF document text
    • https://hafa-verein.de/wp-content/plugins/super-forms/uploads/php/files/d3d5ff093cb9ba4c93761008b7375b4a/95236852619.pdfIn PDF document text
    • https://tecsal.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16096dd98e3d9b---lapizejilenapulufina.pdfIn PDF document text
    • http://carroll1975.com/clients/4/4e/4e2b018d07aaa5a30c3e4fca1c7a8df7/File/juriri.pdfIn PDF document text
    • https://adbadog.com/wp-content/plugins/super-forms/uploads/php/files/abfde241bd502ff10f515207e8b729bb/fipekikepul.pdfIn PDF document text
    • http://www.x454.com/wp-content/plugins/super-forms/uploads/php/files/607frsho197gnbg8o8ime2lli4/62247170874.pdfIn PDF document text
    • http://pspectr.ru/userfiles/file/tarunewomaxuxemamilatosu.pdfIn PDF document text
    • https://luyenthitoeic.info/userfiles/file/64096393676.pdfIn PDF document text
    • http://iaestedresden.de/userfiles/file/91389368709.pdfIn PDF document text
    • http://www.christinemartin.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160985b1bc563a---binijogofozezoxawexigibil.pdfIn PDF document text
    • https://laxmigrouppune.com/wp-content/plugins/super-forms/uploads/php/files/dca353cdad3f096f6dcd1bb3797eb81b/94686451986.pdfIn PDF document text
    • http://vkp.ru/upload/global/file/xazajubatabafuvexima.pdfIn PDF document text
    • http://kondicionery-dolgoprudny.ru/upload_picture/file/47746684819.pdfIn PDF document text
    • http://weberstellen.ch/userfiles/file/59947024936.pdfIn PDF document text
    • http://gezond-trakteren.nl/kasteel-doornenburg-img/bestandenfile/84015637368.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=hogwarts+mystery+game+cheatsPDF 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_off0000fe7f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE7F 19312 bytes
SHA-256: 4573530ec9583df5948d93deb923108eda2176103c3a1fca39657b55e505bca4
font_01_sfnt_off000130c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x130C6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000148dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x148DD 10624 bytes
SHA-256: 6866a2755595153f7d791d072b5a16d5ef05a7b82746f82a22980d9ae285a030