Malicious PDF — malware analysis report

Static analysis result for SHA-256 8b899a2ff385353f…

MALICIOUS

PDF

71.4 KB Created: 2021-09-26 07:27:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 19d21063a78b7766e3d2aa01bf1c60ec SHA-1: 6966f36d167bf7ede459462b51ca220ef354567c SHA-256: 8b899a2ff385353f634e09bda9781fdc36483a7337b981263cb9d06d0a620869
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Heuristics indicate the document functions as a link farm, directing users to multiple external URLs, some hosted on compromised CMS platforms. The presence of numerous links, including one pointing to a compromised WordPress upload, strongly suggests a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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://alternativecarrepair.nl/userfiles/file/49006112575.pdf In PDF document text
    • http://xn--nellieskche-0hb.de/userfiles/file/4710628632.pdfIn PDF document text
    • http://gwtcs.org/Content/uploads/files/vikusamosaratevavu.pdfIn PDF document text
    • http://chanakyaaerospacedefence.com/userfiles/file/83995050794.pdfIn PDF document text
    • https://www.ventisilva.com.br/ckfinder/userfiles/files/walibinowemuxalujasugade.pdfIn PDF document text
    • https://granitabrasive.hu/editor_up/95991908742.pdfIn PDF document text
    • http://smartvoicecom.com/userfiles/mekifa.pdfIn PDF document text
    • http://www.kidnuri.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140eb6fc3c65---80677243801.pdfIn PDF document text
    • http://reutlinger.pl/userfiles/file/xaxevonarawivatajekufuf.pdfIn PDF document text
    • https://rrhh.fronteraliving.com/imagenes/contenidos/files/pifitamumifin.pdfIn PDF document text
    • http://aajude.pt/backoffice/ckfinder/userfiles/files/savefodetujofe.pdfIn PDF document text
    • http://c2r.su/uploadfiles/file/2021091515583073499.pdfIn PDF document text
    • https://otdelkamos.ru/wp-content/plugins/super-forms/uploads/php/files/f10f7ec62e5183676d6dbacddef2bed8/69324005692.pdfIn PDF document text
    • http://olsztyntransportmedyczny.pl/userfiles/file/faletagupizimuru.pdfIn PDF document text
    • http://xetaihyundai.net/upload/files/rejive.pdfIn PDF document text
    • https://hijaulumut.com/contents/files/91892059145.pdfIn PDF document text
    • https://ip-kamera-rendszer.nuttydog.hu/ckfinder/userfiles/files/juxamozelega.pdfIn PDF document text
    • https://www.limratechnologies.net/wp-content/plugins/formcraft/file-upload/server/content/files/16143f465df049---disigol.pdfIn PDF document text
    • http://slowjamsundays.com/wp-content/plugins/formcraft/file-upload/server/content/files/16146fbd36ad17---gajimuxumodizefinulilasak.pdfIn PDF document text
    • http://stopguepes72.fr/userfiles/file/60724244683.pdfIn PDF document text
    • http://gima.ge/admin/ckeditor/ckfinder/userfiles/files/82919521045.pdfIn PDF document text
    • http://dighakanchaninternational.com/FCKeditor/file/sizevofed.pdfIn PDF document text
    • http://hotel-gerard-dalsace.com/upload/document/98600043004.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=happymod+latest+version+apk+downloadPDF 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_off0000b35c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB35C 16772 bytes
SHA-256: 350747d72e32f8eb3a0c60314d32462ed7266dd1081a6e97e5abc8a0714c8798
font_01_sfnt_off0000de60.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE60 10900 bytes
SHA-256: 18d72fe16b8436295b0e8810ef121c29a81f72d6c830b25895383cd5a8ceccac
font_02_sfnt_off0000f79c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF79C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1