Malicious PDF — malware analysis report

Static analysis result for SHA-256 804529565362776a…

MALICIOUS

PDF

86.3 KB Created: 2021-09-04 03:48:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 975b60481fe3813f2d5a4bd238e0a634 SHA-1: e470bbe39ed89e42c7ac6fd1376bae3bbb8b7a4f SHA-256: 804529565362776a5f77f70f993cb95b9471d33c918dc1f09d3c507b2361bd16
156 Risk Score

Malware Insights

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

The PDF contains a large number of links pointing to various websites, many of which are hosted on compromised CMS platforms. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution through these external links. The document body is heavily obfuscated and appears to be non-readable content generated by wkhtmltopdf, providing no direct user-facing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://brylka-kfz.de/wp-content/plugins/formcraft/file-upload/server/content/files/160f5554a6e1b4---85985772017.pdf In PDF document text
    • https://thejasmineway.net/wp-content/plugins/super-forms/uploads/php/files/n6ggnjp1cq8ikniqaod7s8ii2s/24416831252.pdfIn PDF document text
    • https://journeypeople.cc/wp-content/plugins/super-forms/uploads/php/files/253669100479037f9ca68e6d0264c0b0/fokelixon.pdfIn PDF document text
    • http://songhandiban.com/uploadfile/file/2021083115580773499.pdfIn PDF document text
    • https://otartufo.com/ckfinder/tartufofiles/files/biwil.pdfIn PDF document text
    • http://www.canadiantreasurer.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a0b240c46d7---juwalenatiwesamidiwa.pdfIn PDF document text
    • https://insights3.com/wp-content/plugins/super-forms/uploads/php/files/8c848628fd955e595bffefa3c3453513/zuvexobe.pdfIn PDF document text
    • https://auto826.com/uploads/files/64698565981.pdfIn PDF document text
    • https://hoffmanowska.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1606cbd554a9f0---lidutudumadap.pdfIn PDF document text
    • https://alwaysthesame.pt/site/upload/file/digasexewomixepumamanumes.pdfIn PDF document text
    • https://www.truesdalepainting.com/wp-content/plugins/formcraft/file-upload/server/content/files/16116f0f5ead19---85762605214.pdfIn PDF document text
    • http://odnoklassniki-files.ru/images/uploads/files/wagakoruzijibobevegisurog.pdfIn PDF document text
    • https://sfeerweter.nl/userfiles/files/98636699353.pdfIn PDF document text
    • http://nadiadsa.org/userfiles/file/gulisedadatoku.pdfIn PDF document text
    • https://sv-fin.ru/wp-content/plugins/super-forms/uploads/php/files/e81102cb8e2f71d0ded45b312bedd3cb/4429833545.pdfIn PDF document text
    • http://www.hkwebdesign.com.hk/wp-content/plugins/formcraft/file-upload/server/content/files/160e4aab612ebf---32752172087.pdfIn PDF document text
    • http://escolacaritas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bc3dcd1468c---72947081640.pdfIn PDF document text
    • http://deurwater.com/wp-content/plugins/formcraft/file-upload/server/content/files/16097c437ec776---nosadeg.pdfIn PDF document text
    • https://lawpropertyconsultants.co.uk/wp-content/plugins/super-forms/uploads/php/files/2pv88m19h800upk7fjt81pnvgu/vevijufodopigebamubupa.pdfIn PDF document text
    • http://cinstech-inspect-survey.com/fckeditor_userfiles/file/nulalaveragi.pdfIn PDF document text
    • https://goldenparadisestsimons.com/wp-content/plugins/super-forms/uploads/php/files/ad9140b98b97799af964b8adcfb74b1a/jabutinuge.pdfIn PDF document text
    • http://yongqingtech.com/d/files/bevaluneravuzuselakogigut.pdfIn PDF document text
    • http://foto-recepty.sk/images/fotky/nijubuzasokemopomofixune.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=advantages+of+focus+group+pdfPDF 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_off0000edf4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDF4 10804 bytes
SHA-256: 066825a5ae7fdd574315a21d128f0b8e74b04893fd126fb426901dcace847108
font_01_sfnt_off000106e3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106E3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011ef5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11EF5 17224 bytes
SHA-256: 7c2c4a268f4b9f4d86248b103332cfa926ef2f0fb2ee8a9fd548a4c70af431ba