Malicious PDF — malware analysis report

Static analysis result for SHA-256 b87c795a5578b9e8…

MALICIOUS

PDF

75.7 KB Created: 2021-06-18 03:28:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-14
MD5: 0848e431825ef2bbba57f5080f3e6c2c SHA-1: 4d0c9b9973cd341c4d28256210e63234e2f85ac7 SHA-256: b87c795a5578b9e8a7456c33bc3e1419f8e3be36ab91c40f32dcd0c490a2eece
156 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many of which are hosted on compromised CMS platforms or appear to be part of a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The document body is heavily obfuscated and does not provide clear textual lures.

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 http://www.iqubz.com/wp-content/plugins/formcraft/file-upload/server/content/files/160828fdd58197---pamososerizitubupel.pdf In PDF document text
    • http://www.leesii.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607212110aadf---84906556052.pdfIn PDF document text
    • http://kaztelcom.kz/ckfinder/userfiles/files/89694908014.pdfIn PDF document text
    • https://wholisticvibrations.com/wp-content/plugins/super-forms/uploads/php/files/b7dffacf690d90a7983dbda15001fe36/dusonoj.pdfIn PDF document text
    • http://ixtvs.de/_upload_bilder/_filemanager/file/gusofudovowedabagudumuva.pdfIn PDF document text
    • https://www.hospedeagora.com.br/wp-content/plugins/super-forms/uploads/php/files/92q1civ2havfiq022lpmehsr25/losuferokef.pdfIn PDF document text
    • http://altaprecision.com/userfiles/file/63630260001.pdfIn PDF document text
    • http://rusiuojigalvoji.lt/wp-content/plugins/formcraft/file-upload/server/content/files/1609dc5b8f056e---basixudevazefewot.pdfIn PDF document text
    • http://4reality.cz/userfiles/files/19493126988.pdfIn PDF document text
    • https://homeaestheticsllc.com/wp-content/plugins/super-forms/uploads/php/files/e3df70063091eab95cb54f4d740bfdf6/tesor.pdfIn PDF document text
    • https://fourseasons.events/wp-content/plugins/super-forms/uploads/php/files/3c2c38ee44e7970682201d550180c0d9/durezadiluduperig.pdfIn PDF document text
    • https://goldengrowers.com/wp-content/plugins/super-forms/uploads/php/files/c6935f1ac2f5d0331c1649c6a53e462b/41433291997.pdfIn PDF document text
    • https://advance-pack.com/editor_upload/file/66787714612.pdfIn PDF document text
    • http://learningkey.org/userfiles/74071580291.pdfIn PDF document text
    • https://www.truesdalepainting.com/wp-content/plugins/formcraft/file-upload/server/content/files/16091b268bc0b4---xelidovilutokulewo.pdfIn PDF document text
    • http://english-island.pl/wp-content/plugins/super-forms/uploads/php/files/6hsvqib7uphdg6rk0sflbdflg6/vuxufetoxatavuxofanaviwek.pdfIn PDF document text
    • https://www.accidentinjuryalbuquerque.com/wp-content/plugins/super-forms/uploads/php/files/1frgqb9e75e4023tk705p5s50n/kugikozowa.pdfIn PDF document text
    • http://blissrenewbeauty.com/newerac2c/userfiles/file/movopager.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=my+three+sons+season+12PDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000eaa1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEAA1 5032 bytes
SHA-256: 8346c6f39868de3f3a52a38f5f3550fa708272e23b7c1b1150bfc9fae5e462fb
font_01_sfnt_off0000fbc9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBC9 11360 bytes
SHA-256: b2f96f40b02bcd74fb82fbf2525c0850f867b048a7996c5b1d61e0afb9c0bd9b