Malicious PDF — malware analysis report

Static analysis result for SHA-256 a657445432b2b901…

MALICIOUS

PDF

84.5 KB Created: 2021-09-09 00:47:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: e2618bf17fd818c13d417885017be913 SHA-1: 692d4979c43484afbaf5d44e08881feb0f8c046e SHA-256: a657445432b2b9013c93da02ce41c518ef5b6012011c3799af377b091c6b5cdd
156 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier indicating a high probability of maliciousness. The heuristics indicate the document functions as a link farm, directing users to compromised websites or potentially malicious content, which is a common tactic for phishing or malware distribution. No scripts were extracted, but the PDF structure and embedded URLs suggest an attempt to redirect users to external malicious resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://euskararenginkana.eus/files/galeria/files/72297602541.pdf In PDF document text
    • https://kemxoi.vn/app/webroot/files/images/pages/files/56218410716.pdfIn PDF document text
    • http://portamarioarchitetto.eu/userfiles/files/dipegut.pdfIn PDF document text
    • https://lyna-garage.com/htdocs/cljr/data/files/47118575134.pdfIn PDF document text
    • https://www.caesarstravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130521fad3fd---guradiderefuvipiriravaz.pdfIn PDF document text
    • https://www.wemservice.com/ckfinder/userfiles/files/61022535157.pdfIn PDF document text
    • http://miryangpension.com/FileData/ckfinder/files/20210901_D334EA01681A07BF.pdfIn PDF document text
    • http://krakowska98.com/zdjecia/fck/file/roxemuzo.pdfIn PDF document text
    • http://icmasistemas.com/userfiles/files/67260041508.pdfIn PDF document text
    • https://nls.vn/upload/files/vexuwamivumijumogefap.pdfIn PDF document text
    • http://ylpqzl.com/ckfinder/userfiles/files/97009062354.pdfIn PDF document text
    • https://fitnessrev.net/wp-content/plugins/super-forms/uploads/php/files/gntmphphsf66mnb1tnisrlhhdg/zugezabiwufoniza.pdfIn PDF document text
    • https://kuechentreff-schmid.de/wp-content/plugins/super-forms/uploads/php/files/vq4udu40evs5th8efc31dfakpq/50436221400.pdfIn PDF document text
    • https://msiutilities.net/documents/4450298775.pdfIn PDF document text
    • http://www.catalogodecineargentino.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613080ffbe431---10427253116.pdfIn PDF document text
    • https://titishop.co/upload/files/95033920671.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137984c450bc---retakikavukixoto.pdfIn PDF document text
    • https://pcetravel.com/files/file/pafosikevolo.pdfIn PDF document text
    • http://shopphutungmayphat.com/upload/img/files/jixodunegog.pdfIn PDF document text
    • https://ocw.tw/uploads/files/65746174139.pdfIn PDF document text
    • https://dejavuruse.com/userfiles/file/13634510446.pdfIn PDF document text
    • http://mwflower.com/upimagesfile///31226942590.pdfIn PDF document text
    • http://telegid.tv/userfiles/files/42680985399.pdfIn PDF document text
    • https://ashasuchikala.com/ckfinder/userfiles/files/fukoragefewebadob.pdfIn PDF document text
    • https://esterkins.de/ckfinder/userfiles/files/zawuwawiv.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=best+fighter+jet+game+for+androidPDF 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_off0000e7e9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7E9 10936 bytes
SHA-256: fc5a1885e9c3d1552046dd41093907304699f4099d071ccb972607949ee4e193
font_01_sfnt_off000100da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100DA 17036 bytes
SHA-256: 728ff80f2072c4c8822f7546f2633bf7d027a1c3dc0c9b7276e482240c0ca8f5
font_02_sfnt_off00012c9c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C9C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1