Malicious PDF — malware analysis report

Static analysis result for SHA-256 4ab4d4883d39a1fb…

MALICIOUS

PDF

75.7 KB Created: 2021-09-02 16:57:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 19b52e90e702cd5750efb4d27a71d5ce SHA-1: fedc334cb940a60213ef32540d59898e7d5ff85c SHA-256: 4ab4d4883d39a1fbcd122c1ff351b24817ca5ba85fcb0fa5d51df764b80cf112
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous links to compromised websites, suggesting it functions as a link farm or redirection mechanism to malicious content. The presence of multiple PDF link farm heuristics further supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 http://lulanjina.net/upload/files/xajujo.pdf In PDF document text
    • http://ganan10.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/1610da8e4262c4---12561659630.pdfIn PDF document text
    • https://www.jemelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610b0e87ecbd4---vinosiziw.pdfIn PDF document text
    • https://carthink.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a080d411d80---40917112525.pdfIn PDF document text
    • http://getampedmag.com/ckfinder/userfiles/files/supuvinewivefo.pdfIn PDF document text
    • http://mattstergamer.com/wp-content/plugins/super-forms/uploads/php/files/5g95cv33nueelqeqjnnn7jbaur/jutesafuvite.pdfIn PDF document text
    • http://assushop.com/userfiles/assushop.com/file/pevamimukomen.pdfIn PDF document text
    • http://parkwestresidences.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e4e0236acfc---28865967121.pdfIn PDF document text
    • http://poney-club-romilly-aigre28.fr/userfiles/file/22266685352.pdfIn PDF document text
    • http://zaun-produzent.de/userfiles/file/kisivolomenemalu.pdfIn PDF document text
    • https://pelicanfinancialnetwork.net/ckfinder/userfiles/files/85180707742.pdfIn PDF document text
    • http://archiwum.wyryki.eu/admin/ckfinder/userfiles/files/27851763165.pdfIn PDF document text
    • https://xo-sound.ru/userfiles/file/74694908218.pdfIn PDF document text
    • https://bonpetsupply.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072c7272732f---10236342765.pdfIn PDF document text
    • https://miaousland.fr/ckfinder/userfiles/files/21446868419.pdfIn PDF document text
    • http://www.southforconstruction.com/frontend/web/ckfinder/userfiles/files/nomoxawuvubokiraf.pdfIn PDF document text
    • http://jrpst.pl/userfiles/file/vezagivimezetaruwuxufo.pdfIn PDF document text
    • http://jarosi.hu/files/file/22306847948.pdfIn PDF document text
    • http://www.majorisinvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160ae2c6952b7a---fugidazonozevo.pdfIn PDF document text
    • https://desense.eu/uploads/wysiwyg/files/daguwinulova.pdfIn PDF document text
    • http://www.julitolaschools.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e858e3d7f59---sajugisifu.pdfIn PDF document text
    • http://gesundimjob.at/images/content/files/48787834554.pdfIn PDF document text
    • https://www.ideaklinikbakirkoy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606edc416c89b---kujojowuweg.pdfIn PDF document text
    • http://asja-doll.ru/userfiles/file/59032168149.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=meaning+of+reliability+in+research+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_off0000c329.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC329 11148 bytes
SHA-256: 14959243a4bca2242a986dcb7bd41ba69fbe6a8997d8181d4f8d98644eefcc99
font_01_sfnt_off0000dcb8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCB8 17152 bytes
SHA-256: 0ee741dd1b967700bb6e738df52305be55ee6afc77af1599947026ae3f5a0172
font_02_sfnt_off000108d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108D1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1