Malicious PDF — malware analysis report

Static analysis result for SHA-256 b20a6757ef23933d…

MALICIOUS

PDF

77.9 KB Created: 2021-06-07 11:44:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-07
MD5: 30659b98f1689a022d081e7a3d8a74ec SHA-1: 85776d00913f1294389657e72d7788c18480b449 SHA-256: b20a6757ef23933db898dcf4274c197ba762e8c6f795384163766192ce2bd883
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous links to external websites, many of which are hosted on compromised CMS platforms or disposable hosting, indicating a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery. Although no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of a malicious document designed to redirect users to harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://krisoc.ru/uplcv?utm_term=ejercicios+de+fricci%25C3%25B3n+est%25C3%25A1tica+resueltos+pdf PDF link annotation
    • https://aawyx.com/sites/default/imageuser/file/ponirilolesipefu.pdfIn PDF document text
    • http://krindustria.com.br/site/wp-content/plugins/formcraft/file-upload/server/content/files/16081a9412e4f9---lefejimewizuwewupume.pdfIn PDF document text
    • https://muratay.nl/userfiles/file/luxobotidaxu.pdfIn PDF document text
    • https://anthonygillant.com/userfiles/file/59873627626.pdfIn PDF document text
    • https://www.tifdip.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a0264844587---fofasi.pdfIn PDF document text
    • http://www.argentum.com/wp-content/plugins/super-forms/uploads/php/files/tkkejmub1qe77u5cgcqd31b5nu/82875407322.pdfIn PDF document text
    • https://tamtam.com.ua/wp-content/plugins/super-forms/uploads/php/files/d91be644cf2bacf0c2773386bc98a599/83692227869.pdfIn PDF document text
    • https://rclurie.com/wp-content/plugins/super-forms/uploads/php/files/6004235b35706927ec187c7f316c7798/18023495717.pdfIn PDF document text
    • https://globalclassic.org/wp-content/plugins/super-forms/uploads/php/files/942tlie8dhmb302bp80rb1cuuu/11612401847.pdfIn PDF document text
    • http://benardoutlite.com/admin/fckeditor/fckdata/file/vagogukoxemutofoka.pdfIn PDF document text
    • http://for-rent-aalst.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a672560ec08---90547399677.pdfIn PDF document text
    • https://propbrains.com/wp-content/plugins/super-forms/uploads/php/files/iivtr1gae3pthb56gtvvb7ke42/wusidadijuvivegexawo.pdfIn PDF document text
    • http://www.rec39.ru/wp-content/plugins/super-forms/uploads/php/files/6c8dc1e099cf1a4d85a5d0aa188950a0/63811112433.pdfIn PDF document text
    • http://kasintorn.com/images/upload/files/89909401303.pdfIn PDF document text
    • http://ipsgroupjjn.org/userfiles/file/joxaf.pdfIn PDF document text
    • http://beiks.info/public/file/8940426376.pdfIn PDF document text
    • https://auf.vn/wp-content/plugins/super-forms/uploads/php/files/9lgadqucs5gb337o4g15j9cos0/temajow.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn 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_off0000d902.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD902 5552 bytes
SHA-256: 1f8a55629170a2fb6ad4921188ff5c5c87665b0d48c52498927d9989e476ea4a
font_01_sfnt_off0000eb25.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB25 12080 bytes
SHA-256: c8d182419348461a51db501b90daeb1a27b5a96f0ef34fcded112df886f6dc39
font_02_sfnt_off0001133a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1133A 16036 bytes
SHA-256: 9559dd1bd908241551916101fda3d445a26f5c4b506a1423f23393456f9d5940