Malicious PDF — malware analysis report

Static analysis result for SHA-256 df0c90eed7ce7b02…

MALICIOUS

PDF

76.5 KB Created: 2021-09-23 02:45:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: e81dc042789035715be1ceb54ecddaf5 SHA-1: e0bd6c70d7aaa54f847a1b8e56da89253e5b172b SHA-256: df0c90eed7ce7b029478b66b528b2012e01059c5af99738dfc6a9dcdd2674d1e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to compromised CMS upload storage or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to deliver second-stage payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://synerhu.ru/uplcv?utm_term=t95+max+custom+firmware PDF link annotation
    • https://www.esicm-old.org/admin/lib/ckfinder/userfiles/files/soladoresi.pdfIn PDF document text
    • http://domosplast.hu/files/file/41391241564.pdfIn PDF document text
    • http://wksystems.net/HotelEstimator/userfiles/file/49594296025.pdfIn PDF document text
    • https://metroguards.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1613ba8746806e---43673262764.pdfIn PDF document text
    • http://dambi.pl/userfiles/file/novosileneto.pdfIn PDF document text
    • http://criminisiepartners.it/userfiles/files/zugeg.pdfIn PDF document text
    • http://sanzmendia.com/userfiles/files/46173830911.pdfIn PDF document text
    • http://www.galiantsolutions.com/emailimages/file/lajiwunuvuz.pdfIn PDF document text
    • https://taperagi.com/contents/files/13722890793.pdfIn PDF document text
    • https://gccpay.net/wp-content/plugins/super-forms/uploads/php/files/80ce818a98f6c539141bfe4679d8554e/mabalupupejapubafulek.pdfIn PDF document text
    • https://jooli.ru/ckfinder/userfiles/files/piwedukikabuferen.pdfIn PDF document text
    • https://beytarimcilik.com/admin/editor_resim/file/79520791153.pdfIn PDF document text
    • http://viettranslators.com/webroot/img/files/92318423221.pdfIn PDF document text
    • http://lycee-elm.org/userfiles/file/diriwafafuresewofinupefod.pdfIn PDF document text
    • http://svs-pm.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ffb5d65339---82505176159.pdfIn PDF document text
    • https://worldkelo.com/wp-content/plugins/super-forms/uploads/php/files/1584b29fd2bd2998a620ae7c7c099ef0/69652815444.pdfIn PDF document text
    • https://smoothnomad.com/wp-content/plugins/super-forms/uploads/php/files/ns2uvogv9mdht572afdfvcnfsu/49646598136.pdfIn PDF document text
    • http://railwaysrailroads.com/upload_files/files/toval.pdfIn PDF document text
    • https://holocaustresearch.pl/nowy/photo/file/robafowolu.pdfIn PDF document text
    • http://lagostena.it/userfiles/files/vanuvud.pdfIn PDF document text
    • http://kientrucsangtrong.com/plus/files/kidodanaletevuxunebamen.pdfIn PDF document text
    • http://geostudio.eu/userfiles/files/13808157172.pdfIn PDF document text
    • http://studioprogettoarchitettura.eu/userfiles/files/28075133356.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_off0000c4da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC4DA 17632 bytes
SHA-256: 11d958b0dcd63138503e161a62dbca82ecc7e43a54ebd8010773fb76c844fc4c
font_01_sfnt_off0000f29e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF29E 10900 bytes
SHA-256: c9993c261e5d6086a1f3ce8f54335429d7d31bf156968f95739431e34298f602
font_02_sfnt_off00010c18.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C18 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1