Malicious PDF — malware analysis report

Static analysis result for SHA-256 d36f87bbb08ab836…

MALICIOUS

PDF

79.9 KB Created: 2021-10-21 03:02:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 49cb7a8d771377eb745ccad70094455b SHA-1: 7046c88bc389addae190493616fa7a9a1899e922 SHA-256: d36f87bbb08ab83612a247f3ae05f50cde9ae8d90177151349f0e34e09e294f3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF document was flagged by a machine learning classifier and ClamAV as malicious. It contains numerous embedded URLs, many of which point to compromised CMS upload storage or are part of a link farm on disposable hosting, suggesting a phishing or malware distribution attempt. While no scripts were explicitly extracted, the nature of the embedded links and the overall detection strongly indicate a malicious intent to redirect users to harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://rimsball.com/ckfinder/userfiles/files/55460757885.pdf In PDF document text
    • http://npcbalkan.net/ckeditor/ckfinder/userfiles/files/1451016109.pdfIn PDF document text
    • http://tbm-mova.by/images_from_html_editor/file/fikuwupakefa.pdfIn PDF document text
    • http://edwindijk.nl/home/edijk/domains/edwindijk.nl/public_html/uploads/file/93417566242.pdfIn PDF document text
    • http://yakutiaprime.ru/SITE/files/editor/file/tozukovadowiz.pdfIn PDF document text
    • https://et-auditing.com/userfiles/files/91527996863.pdfIn PDF document text
    • http://awarelaxcentrum.cz/user_files/file/xazokosibuwiwusu.pdfIn PDF document text
    • http://sor1310.com/userfiles/file/1510134853.pdfIn PDF document text
    • http://paymentsbusiness.ca/wp-content/plugins/formcraft/file-upload/server/content/files/161432198554ea---jugekizazaxawaxak.pdfIn PDF document text
    • http://www.sname.org.tw/sname/ckfinder/userfiles/files/nagukemigubedi.pdfIn PDF document text
    • http://wxmx.cn/upload/ckimg/files/202110040647118467.pdfIn PDF document text
    • http://aquamedia.cn/ckfinder/userfiles/files/tinowopusisolufuf.pdfIn PDF document text
    • https://7foro.exceltur.org/exceltur_nuevo/ckfinder/userfiles/files/pozubolukibifafojoxosiluv.pdfIn PDF document text
    • http://demenagements-remond.fr/userfiles/file/20210901070137.pdfIn PDF document text
    • https://appchecar.com/ckfinder/userfiles/files/totoliwunetezavafem.pdfIn PDF document text
    • https://pnvvr.ro/userfiles/file/51140974385.pdfIn PDF document text
    • http://turningpointdigital.com/cote_dor_import/admin/ckfinder/userfiles/files/vedamematulitaj.pdfIn PDF document text
    • http://bascobrunswick.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16132c50fa5c00---68593965885.pdfIn PDF document text
    • http://status-go.net/gfx/userfiles/files/54426560904.pdfIn PDF document text
    • http://www.thelawchamber.com/wp-content/plugins/formcraft/file-upload/server/content/files/16164660fb955e---kuwapavigumu.pdfIn PDF document text
    • http://tillyardci.com/userfiles/file/lanevekat.pdfIn PDF document text
    • http://altiro.nl/home/tjerk/file/gerodopumanijijapekedesa.pdfIn PDF document text
    • https://linhngapt.vn/upload/files/67390406436.pdfIn PDF document text
    • http://emannsltd.com/userfiles/78819473795.pdfIn PDF document text
    • http://feedproxy.google.com/~r/Xvkpad/~3/4dZi1sgP-vI/uplcv?utm_term=best+themes+for+powerpointPDF 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_off0000d476.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD476 10552 bytes
SHA-256: df8b9e535d388b2047b5f936dd5edeb583017d355ebe7454daef8447850b35d5
font_01_sfnt_off0000ec6a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC6A 17740 bytes
SHA-256: 189fdf3f7ef62db4b52fc66b74f11eb1b4834377e8ca9043ec3e57d20e3f7335
font_02_sfnt_off00011a6b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A6B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1