Malicious PDF — malware analysis report

Static analysis result for SHA-256 dad4c4a799ad98ff…

MALICIOUS

PDF

76.7 KB Created: 2021-09-20 00:14:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 5cb8a1588b4877a9888adcc340329bf3 SHA-1: 64f210fa440362275fe4fe0b29ced4fcd42e46c9 SHA-256: dad4c4a799ad98ff5206b4dcd810c3db3b93603fa563dab5b2112c3749edf608
156 Risk Score

Malware Insights

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

The PDF was flagged by ClamAV as Pdf.Phishing.Trojan and a machine learning classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm, with multiple URLs pointing to compromised CMS uploads and disposable hosting, suggesting an attempt to distribute malicious content or phish users. The document body is heavily obfuscated and unreadable, providing no further context.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://coretry.ru/uplcv?utm_term=barron%27s+ielts+superpack+2019+pdf PDF link annotation
    • http://dhleisure.com/ckupload/files/22676514235.pdfIn PDF document text
    • https://socardan.com/userfiles/files/xuzomizaluzokuzasoja.pdfIn PDF document text
    • http://podhoru.cz/userfiles/file/18123870180.pdfIn PDF document text
    • https://www.spitalmoldovanoua.ro/ckfinder/userfiles/files/jabejopesoxinamibegatetux.pdfIn PDF document text
    • https://sandp-engineering.com/ckfinder/userfiles/files/28925070791.pdfIn PDF document text
    • http://georgewongdesign.com/gwd/upload/files/37256804336.pdfIn PDF document text
    • http://skolicka.eu/foto/images/file/titutifi.pdfIn PDF document text
    • https://whiteplacard.com/UserFiles/file/zepomezalebe.pdfIn PDF document text
    • https://designclarf.it/file/97238166560.pdfIn PDF document text
    • https://grootformaatspandoeken.nl/userfiles/file/pujunolamojupawalido.pdfIn PDF document text
    • http://dom-2000.ru/ckfinder/userfiles/files/gunosofuradelifined.pdfIn PDF document text
    • http://jmvlpslimited.com/ci/userfiles/files/82349590282.pdfIn PDF document text
    • http://kingkady.com/uploadfile/files/63355380283.pdfIn PDF document text
    • http://blesk-stroy.ru/userfiles/files/63953483326.pdfIn PDF document text
    • http://rockpapersun.com/upload_mce_image/file/jamuw.pdfIn PDF document text
    • http://z500.si/files/81638672900.pdfIn PDF document text
    • https://menokatea.com/ckfinder/userfiles/files/rigixoguku.pdfIn PDF document text
    • http://spbi.cz/res/file/bumejafarikuberobofegisi.pdfIn PDF document text
    • http://gachmenminhchien.com/media/ftp/file/zobiwunurajutakub.pdfIn PDF document text
    • http://serendipityorlando.com/wp-content/plugins/formcraft/file-upload/server/content/files/16142710400dd4---32649527004.pdfIn PDF document text
    • https://inlandautorepairmurrietaca.com/wp-content/plugins/super-forms/uploads/php/files/2cc514a32fce8964eaed9799be24d1f9/19346778248.pdfIn PDF document text
    • https://study-go.info/wp-content/plugins/super-forms/uploads/php/files/d80b0fbafda22871261f7e6ebe90c0dc/72682065512.pdfIn PDF document text
    • 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_off0000c794.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC794 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000dfab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFAB 11352 bytes
SHA-256: edacbd4edfb24fc9240c3f47d067ea9a378f12d65ca4800135a814d9c0f636fd
font_02_sfnt_off0000faa7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFAA7 16508 bytes
SHA-256: e379d1d6ffaaf30c37322738a1669c966da10cc7df748e996f9cc1e21e6b0de7