Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf8094642fde069b…

MALICIOUS

PDF

76.7 KB Created: 2021-06-10 16:17:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: 6134c373b75f35450db020121cd35889 SHA-1: 39f3fde691d7754f7f7b86d7ffe12cf72ea3afee SHA-256: cf8094642fde069b2e492b840807dd279c7bf4031711495dda09ad045bd6a719
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics as a link farm pointing to compromised WordPress sites, and ML classifiers also identified it as malicious. The embedded URLs suggest a phishing or malware distribution scheme, likely delivered as a spearphishing attachment. The ClamAV detection further confirms its malicious nature.

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://archism.ru/uplcv?utm_term=solubility+curve+practice+problems+answer+key PDF link annotation
    • http://www.bewegeninarnhem.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1609aa9b5503c5---nuketanotuniki.pdfIn PDF document text
    • https://www.hemoroidklinigi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075eebdeb4b9---najigugudozixib.pdfIn PDF document text
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b70b709596---78964011689.pdfIn PDF document text
    • https://wacee.net/wp-content/plugins/formcraft/file-upload/server/content/files/1608cd31ab7062---mowebuwasewijadikuvu.pdfIn PDF document text
    • https://www.davidcosz.de/wp-content/plugins/super-forms/uploads/php/files/h9fb97nqj90gatidjaodcrl9f2/37085085461.pdfIn PDF document text
    • http://ipvoicenj.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f92c58f618---82645184248.pdfIn PDF document text
    • http://pavcargo.ru/wp-content/plugins/super-forms/uploads/php/files/704da9cb51183b15850ed1abc1082105/niluxezipiworirinagofuva.pdfIn PDF document text
    • https://www.diktu.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a022f54d2e4---44100380988.pdfIn PDF document text
    • http://accomplishtheimpossible.com/userfiles_ati/file/86725032120.pdfIn PDF document text
    • http://atol-res.pl/uploads/file/tewog.pdfIn PDF document text
    • http://movementlab.dk/userfiles/file/9428419125.pdfIn PDF document text
    • http://kystop.com/wp-content/plugins/super-forms/uploads/php/files/m88valfdjjieh01b6vulgh0933/zidugowola.pdfIn PDF document text
    • https://qamarapps.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b89dd939c51---78380657730.pdfIn PDF document text
    • https://www.sblending.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160c18e0cae40f---bineferifimofopuj.pdfIn PDF document text
    • https://www.infratechgroep.nl/wp-content/plugins/super-forms/uploads/php/files/1272167a41b84ce300f79720bcc0297d/11639541968.pdfIn PDF document text
    • https://gservicepz.com/wp-content/plugins/super-forms/uploads/php/files/62910b4043e6c5dea3b6e99ce3a8efc1/34716767064.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

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000edd8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDD8 5640 bytes
SHA-256: ac4547bbfc9e69ec8a1e8c35ec0df33d918636026e5c981a887eb343732e2666
font_01_sfnt_off0001010c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1010C 10624 bytes
SHA-256: c82d067dc543c86d699412f7aafa49bf8b6dddd7ad71ffea2c2f16f6fd304971