Malicious PDF — malware analysis report

Static analysis result for SHA-256 c879ebae3b50a444…

MALICIOUS

PDF

75.1 KB Created: 2021-09-27 17:48:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: bd65be7826a1369a6af6c3e009e6bbc9 SHA-1: 69c4a7f91ef77088b1facccd69030538916bb6a3 SHA-256: c879ebae3b50a4447853d0b3757203a6279ccdb010cbeb5de901fc6f9809126c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is a PDF that contains a large number of external links, many of which point to other PDF files hosted on various domains. This structure is indicative of a link farm designed to obscure the ultimate destination or to distribute further malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://krisoc.ru/uplcv?utm_term=ota+zip+file+for+android+tv+box PDF link annotation
    • https://pamukoglu.com/userfiles/file/71559315533.pdfIn PDF document text
    • https://adproissy.emailingmanager.com/uploads/editor/file/61074966613.pdfIn PDF document text
    • https://sieuthimaytinhcu.vn/upload/files/mabeba.pdfIn PDF document text
    • http://ddaengshop.com/ckupload/files/pilibefolerexipatikix.pdfIn PDF document text
    • http://suachuaspa.com/upload/images-content/files/ragumoro.pdfIn PDF document text
    • http://sherwoodchambergolf.org/ckfinder/userfiles/files/zoduvuwaguv.pdfIn PDF document text
    • http://drvision.org/wp-content/plugins/formcraft/file-upload/server/content/files/16145429d4915d---birufewifuluwikatofurimow.pdfIn PDF document text
    • http://studionegro.net/userfiles/files/pofojuwomenesi.pdfIn PDF document text
    • http://shortguycentral.com/ck_uploads/files/39003397928.pdfIn PDF document text
    • http://mspchicagolaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/dusajedevovalimipajodobe.pdfIn PDF document text
    • http://tourbusan.net/FileData/ckfinder/files/20210918_E6951BEE00E0590C.pdfIn PDF document text
    • http://kondicionery-domodedovo.ru/upload_picture/file/32585800867.pdfIn PDF document text
    • http://honghuibio.com/d/files/99087123081.pdfIn PDF document text
    • http://www.pethouse.es/ckfinder/userfiles/files/jisolevenom.pdfIn PDF document text
    • https://husvagnsexpo.se/wp-content/plugins/formcraft/file-upload/server/content/files/161386469e76d8---36560606071.pdfIn PDF document text
    • https://migger.dk/userimages/file/rawugojenefobifuxolilin.pdfIn PDF document text
    • http://giaodantanthaison.com/Images_upload/files/1137390081.pdfIn PDF document text
    • https://hotelristorantenovecento.it/wp-content/plugins/super-forms/uploads/php/files/459420c06585cf9f784da94bb6bdc005/35788401095.pdfIn PDF document text
    • http://king-tableware.com/uploads/files/202109140531583472.pdfIn PDF document text
    • http://mgocsm.in/userfiles/file/15329343318.pdfIn PDF document text
    • http://tznjl.com/userfiles/files/doloduxuvowukemok.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_off0000ba70.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBA70 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d282.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD282 19480 bytes
SHA-256: 6d70c6699e1eb09904033bc20d3b45ffe99cc3074d999445f14ab423671fc078
font_02_sfnt_off0001061c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1061C 10716 bytes
SHA-256: 90c0d797079a44b2bcb64169f519b485b8d37f65d8737b3c672c12cbc0626fe7