Malicious PDF — malware analysis report

Static analysis result for SHA-256 9e7335be42ef66e5…

MALICIOUS

PDF

84.1 KB Created: 2021-08-16 08:23:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: ef07678f35bbbef1c4af2cb3f17a63d7 SHA-1: 46c0adfeff042b70872649538c467fdd4c64d9a3 SHA-256: 9e7335be42ef66e532ce05f2f6b591e125d287620f095a60d0986074bbde3969
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains a large number of embedded URLs, many pointing to compromised WordPress sites, suggesting a link farm designed to redirect users to malicious content. 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 0.9978

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://catamma.ru/uplcv?utm_term=9.+s%C4%B1n%C4%B1f+fizik+kuvvet+ve+hareket+konu+%C3%B6zeti PDF link annotation
    • https://rrvchefs.com/wp-content/plugins/super-forms/uploads/php/files/bfca8e331f95231b3f37c30696064a8c/15737668021.pdfIn PDF document text
    • http://totaleclipsenv.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ba1e6728aeb---palibatanibiji.pdfIn PDF document text
    • http://unsersohn.ch/images/file/58942213165.pdfIn PDF document text
    • https://asi-filter.pl/files/file/raviwomopufejigokedovo.pdfIn PDF document text
    • https://realimpacto.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160bb8462e0cd1---kozefozadesefefopuj.pdfIn PDF document text
    • http://usaoxin.com/userfiles/2021-6/file/zazamoluwifamelek.pdfIn PDF document text
    • https://laxmigrouppune.com/wp-content/plugins/super-forms/uploads/php/files/ce7a75708c7f23776667bc4838a95d98/riladafonoje.pdfIn PDF document text
    • https://trichynext.com/wp-content/plugins/super-forms/uploads/php/files/0e751816666eedac856cd73319273dbd/82567002594.pdfIn PDF document text
    • http://a-kamen.com/userfiles/file/xupurejigapusogoxedegab.pdfIn PDF document text
    • http://www.klpreschool.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609f483b7b916---jevirasupir.pdfIn PDF document text
    • http://www.northeastmarquees.com/wp-content/plugins/super-forms/uploads/php/files/c73b37fa9952e5501b539d719253197d/mepojurefogelujabivuxas.pdfIn PDF document text
    • https://gmonlinestore.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cd2a219f61---26363701387.pdfIn PDF document text
    • https://www.accidentinjurylascruces.com/wp-content/plugins/super-forms/uploads/php/files/jne8h5tof9ldv7l668jtb1c4kj/14644907971.pdfIn PDF document text
    • https://childconcern.in/trila/userfiles/file/57078182541.pdfIn PDF document text
    • https://getlovebooks.com/wp-content/plugins/super-forms/uploads/php/files/ec97ec150e8ca0d90470b73e56e162c0/52447370096.pdfIn PDF document text
    • https://www.stamfordtaxis.com/wp-content/plugins/super-forms/uploads/php/files/ggen9c5tj7440p4qeccbj4jq51/tememipefuza.pdfIn PDF document text
    • http://driver-jazda.pl/upload/file/4539155804.pdfIn PDF document text
    • https://roweryelectra.eu/app/webroot/uploads/file/16225706825602.pdfIn PDF document text
    • https://unique.global/wp-content/plugins/super-forms/uploads/php/files/1058e9882a7224ce6d149f2da835c6ec/51974954375.pdfIn PDF document text
    • http://christembassydocklands.org/wp-content/plugins/super-forms/uploads/php/files/ebd60837dfe74737af4f69284ccef768/3434674002.pdfIn PDF document text
    • http://cabinet-blin.fr/ressource/site-image/files/viratox.pdfIn PDF document text
    • https://baoholaodong24.com/userfiles/file/lalelinigelubafufemunedil.pdfIn PDF document text
    • http://cga82.com/admin/File/bidujigixubezew.pdfIn PDF document text
    • https://musikkursus.dk/userfiles/file/pesuvurinelagipebofego.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_off0000df88.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF88 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f79f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF79F 10980 bytes
SHA-256: 28b1f31b30b724014cfb7c63d8b6a0b43961948cc4a93e6b3766d54c8e4c87c2
font_02_sfnt_off000110b8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110B8 18788 bytes
SHA-256: 4540ad1b15192ada82397db43948761d8c3712e3282657dfb97c59d3a01999a5