Malicious PDF — malware analysis report

Static analysis result for SHA-256 caa7599d6129f4a3…

MALICIOUS

PDF

69.5 KB Created: 2021-09-05 01:22:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: f3f98551bb4c044167e0b86c129f7acc SHA-1: 6e1c0cbeef956b4ac6de7d52d0ad30bce5e6bc60 SHA-256: caa7599d6129f4a3903262a95361bac7a020b525611c7765315f137817e72e0b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed to redirect users to potentially malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware delivery. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://castilloexterior.net/ckfinder/userfiles/files/kukele.pdf In PDF document text
    • http://highlandlynxotic.com/clients/7/73/73cf6ae24f8ea70eb1cbac1dff6b0f9e/File/wixobigajusupar.pdfIn PDF document text
    • http://pfmconsulting.org/survey/userfiles/files/nirogagubewivugonifa.pdfIn PDF document text
    • https://aguiapromocional.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160983d251901a---jetasedavexunag.pdfIn PDF document text
    • http://yokohama-model.com/userfiles/files/11110999442.pdfIn PDF document text
    • https://rffsev.ru/wp-content/plugins/super-forms/uploads/php/files/9e6e3de18adee3f651c647785b9d6227/64163944071.pdfIn PDF document text
    • https://www.msolartop.cz/wp-content/plugins/formcraft/file-upload/server/content/files/1606f4b9e567ab---ronutupexino.pdfIn PDF document text
    • https://www.davidcosz.de/wp-content/plugins/super-forms/uploads/php/files/mb2limt2lsdd2kjm2fb5me876g/42381823832.pdfIn PDF document text
    • https://smartbrand.ro/mm/file/nalon.pdfIn PDF document text
    • http://buyyoutubesubscribers.com/ci/userfiles/files/zimumipobakafelizupun.pdfIn PDF document text
    • http://trivio.it/userfiles/files/22875193210.pdfIn PDF document text
    • https://www.vigo.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160e28bab71f50---seludasejofowifijikipo.pdfIn PDF document text
    • http://underbutter.cz/download/foto/64047018177.pdfIn PDF document text
    • http://biancoacolori.it/userfiles/files/69850938500.pdfIn PDF document text
    • https://scalping.ir/data/files/file/xorikixuludis.pdfIn PDF document text
    • http://lmyc.net/clients/875386/File/94994273582.pdfIn PDF document text
    • https://zabulgaria.org/userfiles/file/4333935686.pdfIn PDF document text
    • http://ghalemdi.com/userfiles/file/petakuji.pdfIn PDF document text
    • https://premium-house.uz/images/file/13902826201.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=gospel+songs+chords+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_off0000afa8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAFA8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c7ba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC7BA 16196 bytes
SHA-256: 57818b45c07becbd536f9ec377ca4ce6e9d08af83135d86fbb2399ad72f51a7e
font_02_sfnt_off0000f15a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF15A 10584 bytes
SHA-256: bffbe48ab9e5b0009618bc4bae96228c2503a424f1ff60f067ef90257caf1b73