Malicious PDF — malware analysis report

Static analysis result for SHA-256 4285b9835e1a5192…

MALICIOUS

PDF

85.2 KB Created: 2021-08-15 18:23:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 8058f152ea947e9f494475aef29a4532 SHA-1: c6a9abea9cf57904d3f3e1ebc805030e4fbc5f92 SHA-256: 4285b9835e1a51927a4007a88a87a952a7f63159e0248edb7935c4c9c9055f79
156 Risk Score

Malware Insights

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

This PDF file was identified as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. It contains numerous links pointing to compromised WordPress sites, suggesting an attempt to redirect users to malicious content or phishing pages. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, indicating it's not intended for human readability but rather as a container for malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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 http://pvsystreports.com/wp-content/plugins/super-forms/uploads/php/files/1dneqfrtc0v70ds3ed44j2pk87/jovuvogodu.pdf In PDF document text
    • http://big-blue-bus.com/pics/fotos/1/file/56736037673.pdfIn PDF document text
    • http://www.carolglassman.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c1184c4b799---48539159946.pdfIn PDF document text
    • http://www.blackhillsdancecentre.com/wp-content/plugins/formcraft/file-upload/server/content/files/1611457af93829---44779140880.pdfIn PDF document text
    • https://glowskincare.net/wp-content/plugins/super-forms/uploads/php/files/e906a518a042c13d79c234fe5700c808/jexazokenuwemozumagekurid.pdfIn PDF document text
    • http://ed-web.cz/userfilesfile/84310065258.pdfIn PDF document text
    • https://unaizahic.com/Files/files/71174281591.pdfIn PDF document text
    • https://tortugafilms.ca/adminfiles/file/tagivile.pdfIn PDF document text
    • https://byocamacho.com/ckfinder/userfiles/files/lutidavadigo.pdfIn PDF document text
    • http://fewo-spreewald-schoetzigk.de/brandenburgtag/img/editor/file/96740488150.pdfIn PDF document text
    • http://tele-video.ru/upload/files/19902731548.pdfIn PDF document text
    • http://clear-es.net/yamituki-n/uploads/files/gabofalubom.pdfIn PDF document text
    • https://technok.cz/wp-content/plugins/super-forms/uploads/php/files/29990bb2554b1948ca06e0978a50b8ec/tipobutizukevedowidobu.pdfIn PDF document text
    • https://www.spoton.pet/wp-content/plugins/super-forms/uploads/php/files/vg093f4mtdhihg46od9d7bi3b9/97934045067.pdfIn PDF document text
    • http://suliaox.com/v15/Upload/file/202181462007161.pdfIn PDF document text
    • http://irmascaritasdejesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/16077ed4156be8---fenopisaxafabafaxodakibe.pdfIn PDF document text
    • http://dossalas.com/wp-content/plugins/super-forms/uploads/php/files/5dbea6658e3ef62e8822c8806029e49b/benemokoxajowukapi.pdfIn PDF document text
    • https://brunoamaranti.it/wp-content/plugins/super-forms/uploads/php/files/0s8qvuh9bcgcef2f9bj41c41n3/xilorewinebakuzebe.pdfIn PDF document text
    • https://sona3elkhair.com/userfiles/file/bulifadoxomukazilipavo.pdfIn PDF document text
    • https://artsketch.ru/wp-content/plugins/super-forms/uploads/php/files/82376714df0487b4efa7cf46694396d4/xuvinoresasufokivoze.pdfIn PDF document text
    • http://www.maarsehoveniers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16081d9490fc8b---54724460815.pdfIn PDF document text
    • https://accuratesearch.com/userfiles/file/muweda.pdfIn PDF document text
    • http://gourmethousemacau.com/UploadFilesfile///kititagur.pdfIn PDF document text
    • https://kalatranslation.co.uk/wp-content/plugins/super-forms/uploads/php/files/oecaepinmorv6tv2nignch5eo8/39605518031.pdfIn PDF document text
    • http://www.combatsim.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160bbe1d972d05---zuxerodotasesidezebuno.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=watch+tidying+up+with+marie+kondo+online+free+subtitlesPDF 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_off0000e54f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE54F 17304 bytes
SHA-256: 5e0480900411c89bc4ebfc3ce49360989dd2863ec75df166b67d07134b161296
font_01_sfnt_off000112b1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x112B1 11592 bytes
SHA-256: d6d92ce8b3a06b628f6fba2e8ee2fea80aae774e4b35ce23543c8314feafdd13
font_02_sfnt_off00012db9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12DB9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1