Malicious PDF — malware analysis report

Static analysis result for SHA-256 a36ecae4870e4589…

MALICIOUS

PDF

82.6 KB Created: 2021-09-07 17:49:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: c19691b6b53f10976dd97cc07ef90c03 SHA-1: 2a83fbfb1ec5dfb40705d18157545fe201eee24f SHA-256: a36ecae4870e4589707f6a5865dd6732f526493404d1ebb3f33d7b9077a64cdf
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, many of which point to compromised CMS upload storage or are hosted on disposable domains, suggesting a link farm designed to redirect users to malicious sites. The PDF structure and embedded links are consistent with phishing or malware distribution tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

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://revucue.com/ckfinder/userfiles/files/6547461271.pdf In PDF document text
    • http://aucoindeshalles.fr/menu/file/77274259591.pdfIn PDF document text
    • https://drivingschoolofnorthtexas.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076c9dad9127---pakolanesa.pdfIn PDF document text
    • http://geodeslaboratori.eu/userfiles/files/sezod.pdfIn PDF document text
    • https://amagi.la/wp-content/plugins/formcraft/file-upload/server/content/files/1606cbf032ee8b---39790936436.pdfIn PDF document text
    • http://vankouwenenmastop.nl/UserFiles/file/vigiwanusuwiwifikerag.pdfIn PDF document text
    • http://asustainable.com/global/file/nutopevefejiperu.pdfIn PDF document text
    • https://bellevuecommunityfoodbank.org/wp-content/plugins/super-forms/uploads/php/files/d301b06cb341f992328dffd5c66a4aed/gofenizuje.pdfIn PDF document text
    • http://faisaltowel.com/survey/userfiles/files/tinexezipatevisawafidekek.pdfIn PDF document text
    • https://www.propertyadvisersaustralia.com/wp-content/plugins/super-forms/uploads/php/files/146922a0e53b064da67c98e3430b4d19/10109928746.pdfIn PDF document text
    • https://alkhairi.co.uk/wp-content/plugins/super-forms/uploads/php/files/c491b2f40f5e184fc3aa4759c2ada371/doxasomomudivo.pdfIn PDF document text
    • http://kleiberit.ru/files/file/91800136742.pdfIn PDF document text
    • https://gmonlinestore.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e44cce7f3d---kavawugigufizewasuvijigo.pdfIn PDF document text
    • http://akinmedikal.com/uploads/file/konetu.pdfIn PDF document text
    • https://adm.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/8dfe76a068ff5ad97dc376f93c377246/18399886401.pdfIn PDF document text
    • http://amadpich.com/userfiles/file/38836867090.pdfIn PDF document text
    • https://sipare.com.ar/wp-content/plugins/super-forms/uploads/php/files/vsoprqj8qk1vg698lt2j63qabg/fedaxapakuwepepudevafete.pdfIn PDF document text
    • https://athensviptour.com/wp-content/plugins/super-forms/uploads/php/files/683f070f2cbcc24d9cb94a86bfe18eca/vupijugojapagavu.pdfIn PDF document text
    • http://oreade-breche.fr/userfiles/file/pawedinidefamolomu.pdfIn PDF document text
    • http://mcutech.net/files/feruza.pdfIn PDF document text
    • https://freedomhypnosisnyc.com/wp-content/plugins/super-forms/uploads/php/files/8eeecb15a2252682419f9c62ee6b4fc7/84341308746.pdfIn PDF document text
    • https://www.fifatravels.com/wp-content/plugins/formcraft/file-upload/server/content/files/161255a4dca9dc---fivifazudomabu.pdfIn PDF document text
    • https://maidintown.co.uk/wp-content/plugins/super-forms/uploads/php/files/9d9e3d689cdf9898cd9bee0f2cd4c5ff/93227330732.pdfIn PDF document text
    • https://bor-diing.com/upload/files/gumedumememudowabonad.pdfIn PDF document text
    • http://filtrydokoparek.pl/img/all/gijupup.pdfIn PDF document text
    • http://coeb.eu/userfiles/files/xexufajo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=verbal+reasoning+worksheets+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_off0000db77.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB77 11064 bytes
SHA-256: 5b2615422e8332dc42b013b8aea55d7d4681b95631eff524bfbaf1973888be1d
font_01_sfnt_off0000f4d2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4D2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010ce4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CE4 18300 bytes
SHA-256: 140220a4915193bb971c2d927ae2a3a3407f001c3e8352e9f077eb960e2964d2