Malicious PDF — malware analysis report

Static analysis result for SHA-256 4a17d51eb179df1e…

MALICIOUS

PDF

71.3 KB Created: 2021-09-12 03:48:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: edf3277ec6d56008378f661e193dd47e SHA-1: 32c65c95e5c51fadbd982c117b921308244d3bac SHA-256: 4a17d51eb179df1e701fec5d1f6906099d2d675abad318ea9457233ecb78e42d
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to compromised websites and disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. No scripts were extracted, but the PDF structure and URL patterns are indicative of a malicious lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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://mvmdigital.gr/files/files/zevukunativijamo.pdf In PDF document text
    • https://chilegastronomia.cl/uploads/userfiles/files/86829465148.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133c84c952e8---xepisowivikem.pdfIn PDF document text
    • http://frutapac.com/ckfinder/userfiles/files/79495252131.pdfIn PDF document text
    • https://kaimano.it/file/zirage.pdfIn PDF document text
    • https://luminex.pl/upload/file/zazatalopatuvugivobijesa.pdfIn PDF document text
    • https://ateneoarbonaida.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d2b1ce6d16---83698360380.pdfIn PDF document text
    • http://ozgu-yapi.com/firma/files/jivoki.pdfIn PDF document text
    • https://threadworx.com/thread/admin/uploads/file/77000566057.pdfIn PDF document text
    • http://barrarioservicos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613be90031b24---nofugapetilifamowosa.pdfIn PDF document text
    • http://amy-tsai.com/images_express/userfiles/files/pijixorifarakujixojopak.pdfIn PDF document text
    • http://satyavnetworks.com/fck_upload_images/file/fijufa.pdfIn PDF document text
    • https://investincarpathians.eu/app/webroot/media/files/delikalurekekifiguzoxijo.pdfIn PDF document text
    • https://daks-96.com/f/uploads/files/67542632459.pdfIn PDF document text
    • http://beamstraffic.ae/amb/userfiles/file/86339105869.pdfIn PDF document text
    • http://n-production.com/upload/fckeditor/file/9542574291.pdfIn PDF document text
    • https://orig-shop-gsm.ro/ckfinder/userfiles/files/96663490419.pdfIn PDF document text
    • https://veritiesinstitute.com/wp-content/plugins/super-forms/uploads/php/files/745c3afecad70edf825b07772d99b128/wudewaxudowarogub.pdfIn PDF document text
    • https://manuscripthandler.com/userfiles/file/zarigadisezifaxava.pdfIn PDF document text
    • http://ed-union05.ru/files/file/dedixogopiwogovi.pdfIn PDF document text
    • http://st03.it/userfiles/files/29544462799.pdfIn PDF document text
    • https://psfund.org/public/uploads/files/cms_files/90251874965.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=cara+membuka+file+apk+di+pcPDF 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_off0000b5f0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB5F0 10656 bytes
SHA-256: d6cd15ebc4602f0a7b24c0692a95711a26d3bf58f6a90b7813663a3e44455893
font_01_sfnt_off0000ce11.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE11 16312 bytes
SHA-256: f0236fe55f5fb8f475236ac7655fa8e17450481e21fed58dc35c9e92fec36f66
font_02_sfnt_off0000f7a9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7A9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1