Malicious PDF — malware analysis report

Static analysis result for SHA-256 4785e540e58b9175…

MALICIOUS

PDF

85.4 KB Created: 2021-09-17 19:16:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 1851b4b1eec038b1bbdd7c1c966bc5cb SHA-1: 8c03a4009ee073c3dcb7177ccd3e5df5bb468380 SHA-256: 4785e540e58b91750d0ec9e53f96967f40d80a0ecfc9354b513c9afbb3893193
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains a link farm with numerous URLs pointing to potentially compromised websites or disposable hosting, designed to redirect users. The presence of embedded URIs and the PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicate a strong intent to direct users to external, likely malicious, resources.

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 http://houstontca.org/Content/uploads/files/80145972056.pdf In PDF document text
    • http://traiteur-ribot.fr/userfiles/file/54780898214.pdfIn PDF document text
    • http://seattlebestteriyaki.com/uploads/files/fizamezezizizesuxajug.pdfIn PDF document text
    • http://braintradingbcn.com/wp-content/plugins/super-forms/uploads/php/files/63703f123bd954f6abc281af54a48bf0/bukozudebutudaxagubumitov.pdfIn PDF document text
    • http://irollee.com/userfiles/file/1491224339.pdfIn PDF document text
    • http://old.bgk-meshkova.com/ckeditor/ckfinder/userfiles/files/jejapeviduzisaze.pdfIn PDF document text
    • https://highlander-inn.com/assets/userfiles/files/19085516154.pdfIn PDF document text
    • https://birudongker.com/contents/files/50205975938.pdfIn PDF document text
    • http://ranch.pl/files/file/satabifiduboja.pdfIn PDF document text
    • http://koreaseals.com/ckfinder/userfiles/files/zabugeme.pdfIn PDF document text
    • http://suportti.com/wp-content/plugins/formcraft/file-upload/server/content/files/161333bbc1fa82---nogijewujesozejupifo.pdfIn PDF document text
    • http://design-klasse.de/ckfinder/userfiles/files/61429506148.pdfIn PDF document text
    • https://bientannamhuy.com/wp-content/uploads/files/39947156304.pdfIn PDF document text
    • http://acrclubinversores.com/files/galeria/files/debejusamirilami.pdfIn PDF document text
    • http://ajej.pretty-match.com/upload/files/goxiguroniganemot.pdfIn PDF document text
    • http://alcantara.cz/data/file/pexodutogota.pdfIn PDF document text
    • https://www.limratechnologies.net/wp-content/plugins/formcraft/file-upload/server/content/files/16135386c256bf---jelopazejoloxerizo.pdfIn PDF document text
    • http://ebslang.net/_UploadFile/Images/file/61520519790.pdfIn PDF document text
    • http://kursverwaltung.fit-n-essen.ch/ckfinder/userfiles/files/61184877285.pdfIn PDF document text
    • https://www.dynasil.com/wp-content/plugins/super-forms/uploads/php/files/430c154765f88a9e64f8ec5fbd16cad7/22704843525.pdfIn PDF document text
    • http://bonsite.nl/phpcmsys/file/14443983806.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=best+mapping+apps+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_off0000ea5b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA5B 10848 bytes
SHA-256: 823002073760f818d43af6d1eae6bd7fffbbea01f3ecbcad24b4eb0cb2a274dc
font_01_sfnt_off00010332.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10332 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011b44.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B44 17240 bytes
SHA-256: d4f28227c549780af4f5942081e0bf90f89d68ebf9d23f78e5a2620a1b29cb5c