Malicious PDF — malware analysis report

Static analysis result for SHA-256 8c51c45fc7a95c10…

MALICIOUS

PDF

88.6 KB Created: 2021-09-07 12:45:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 56d222081604ac3133260391223401ab SHA-1: db10cadea84d3ad883c5559052964faab6d7c736 SHA-256: 8c51c45fc7a95c106fdb632e18a98de7593186a4b5f2de519be4799921180513
156 Risk Score

Malware Insights

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

The sample is a PDF file flagged by multiple heuristics and a machine learning classifier as malicious. It contains numerous links, many pointing to URLs hosted on compromised CMS uploads or disposable domains, suggesting a link farm or phishing lure. The ClamAV detection as 'Pdf.Phishing.Trojan' further supports a malicious intent, likely to redirect users to malicious sites for credential harvesting or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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://prtourusa.com/FileData/ckfinder/files/20210821_1286676B5D537E6E.pdf In PDF document text
    • https://www.hinogas.com/wp-content/plugins/super-forms/uploads/php/files/285h6sq91epr3ccfpfvbi33r89/95400527319.pdfIn PDF document text
    • http://dbjhockeytournament.com/clients/f/f9/f9ff496842c877cbb4522510b668f2a2/File/luromenilekodowutidunek.pdfIn PDF document text
    • http://pressvaluation.net/userfiles/file/sozatut.pdfIn PDF document text
    • https://k-kompany.ru/wp-content/plugins/super-forms/uploads/php/files/175c831d3ea900b75585130aeeb5f7c3/jazetavojatavu.pdfIn PDF document text
    • http://www.hypnotiseur.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072ec1949c8f---ziwewonajitiredi.pdfIn PDF document text
    • https://neavocats.com/wp-content/plugins/super-forms/uploads/php/files/b3abbeb9eb399122bbf5a675a0af05df/67646146283.pdfIn PDF document text
    • http://calisnt.com/uploads/files/60059770122.pdfIn PDF document text
    • https://aryaayur.com/wp-content/plugins/formcraft/file-upload/server/content/files/160981151e9bc9---toxibosopukezukobojigutu.pdfIn PDF document text
    • http://linkipt.com/_UploadEditor/files/migewevepakekesujozoparo.pdfIn PDF document text
    • http://musicfriend.vn/public/default/ckeditor/files/56163459485.pdfIn PDF document text
    • https://mindweave.co.uk/wp-content/plugins/super-forms/uploads/php/files/vtopp27792tic6idohiapi069s/15979023937.pdfIn PDF document text
    • https://www.lipfish.no/wp-content/plugins/formcraft/file-upload/server/content/files/1609ce9eb667ca---lefopisopab.pdfIn PDF document text
    • http://www.drop-lok.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b3af7a1a963---vumijejedoborawipo.pdfIn PDF document text
    • http://tc-antey.ru/uploads/files/1982775319.pdfIn PDF document text
    • http://stellarvvv.ru/ckfinder/userfiles/files/dulixozaxusitilomisudowu.pdfIn PDF document text
    • http://frutapacargentina.com/ckfinder/userfiles/files/31202991667.pdfIn PDF document text
    • http://bestbuyfromindia.com/userfiles/file/90477121073.pdfIn PDF document text
    • https://globaldreamindia.com/webcms/file/wajod.pdfIn PDF document text
    • https://peintures-descours.fr/fichier/files/89131366444.pdfIn PDF document text
    • http://www.kevinbrooks.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160d55a5ea9b8a---41114183084.pdfIn PDF document text
    • https://www.scilights.com/wp-content/plugins/super-forms/uploads/php/files/b8daef8d265bb3e14ad7247cbc677584/87620351276.pdfIn PDF document text
    • http://alphabodysupplements.com/newerac2c/userfiles/file/58378121973.pdfIn PDF document text
    • http://test.uebersetzungen-nesselberger.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607391ed79dbe---26617154108.pdfIn PDF document text
    • http://dmn.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160ba96e944309---99534657941.pdfIn PDF document text
    • http://ngor2-3.com/file_media/file_image/file/57508254591.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=generative+deep+learning+o%27reilly+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_off0000f2f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2F9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010b10.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B10 10760 bytes
SHA-256: 06bc514b5b921b8edcca1dcba75a32604eb1cd1404c4764e34a2150219063586
font_02_sfnt_off000123c7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x123C7 18712 bytes
SHA-256: 9736275a0b9848acd2ab6a1f888d836b98d62f91ba00bea0d652a99424a8ec59