Malicious PDF — malware analysis report

Static analysis result for SHA-256 1cd49373eee18f82…

MALICIOUS

PDF

96.0 KB Created: 2021-07-26 23:06:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 9cb316cfcff8f329e3d1ab023241b5b9 SHA-1: 8cbb96ff97ea580b7501e5830ae482faa7448fb4 SHA-256: 1cd49373eee18f825bdeb2491397bfc21a5bdcc5ab3e9ba6daf7f2787602f6d2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a large number of links, many pointing to websites hosted on compromised WordPress installations or disposable domains, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly support its malicious nature. The embedded URLs and link farm structure suggest an attempt to lure users to external malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

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://for-rent-leuven.com/wp-content/plugins/formcraft/file-upload/server/content/files/160759ca7b61c9---28789333208.pdf In PDF document text
    • http://dossalas.com/wp-content/plugins/super-forms/uploads/php/files/7c6df5f34c0036f2d98e6d2f03cd0004/76439548628.pdfIn PDF document text
    • http://c2r-auto.com/uploadfiles/file/2021051910133373499.pdfIn PDF document text
    • https://psychologgia.pl/Upload/file/zifot.pdfIn PDF document text
    • http://acecaalcoy.com/userfiles/file/vopomutoniragerijone.pdfIn PDF document text
    • http://www.circoloaletrium.it/wp-content/plugins/formcraft/file-upload/server/content/files/16075b63591b8c---56206051764.pdfIn PDF document text
    • http://itaindustrial.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608c43dd9e50f---85750358134.pdfIn PDF document text
    • https://evg-prague.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1608289b30dbe2---xosirijifewojo.pdfIn PDF document text
    • https://www.lang-mayer.de/wp-content/plugins/formcraft/file-upload/server/content/files/16080eaa08a20c---rokiximutidapozoxaz.pdfIn PDF document text
    • https://maconlux.lu/userfiles/files/basokamuwurapa.pdfIn PDF document text
    • https://o-dance.com/upload/files/32761645800.pdfIn PDF document text
    • https://cmottaviproductive.it/uploads/file/31830105492.pdfIn PDF document text
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/160854b6714936.pdfIn PDF document text
    • https://cremyco.com/app/webroot/docs/file/lipij.pdfIn PDF document text
    • http://oishisushigd.com/uploads/files/82182765324.pdfIn PDF document text
    • http://brooklinehs1964.com/clients/6/6a/6a3559cec3eb17f551da2d864c8c85ab/File/34375073784.pdfIn PDF document text
    • http://www.agrosystem.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160c66a19ed41c---80648449640.pdfIn PDF document text
    • http://www.masozilina.sk/ckfinder/userfiles/files/vixikigiduwod.pdfIn PDF document text
    • http://xn--clinicaquirogavilario-vbc.com/wp-content/plugins/super-forms/uploads/php/files/chgkq986l8qn8v05inf9imnr56/64712947175.pdfIn PDF document text
    • https://certifiedmoversinc.com/wp-content/plugins/super-forms/uploads/php/files/2af1f97faf0c1e853a3ed386168bf9bc/86096922679.pdfIn PDF document text
    • https://ipcare.nl/wp-content/plugins/super-forms/uploads/php/files/7aqqb8pif6ss0d1ft6hqftg49j/73739072006.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b2774ee4d4---naxoweg.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=return+to+work+after+maternity+leave+letter+templatePDF 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_off00011283.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11283 10852 bytes
SHA-256: 7c5fb7dc5b8fd999e0201f152d3cc2988b3bbdbf0d5bc78bff6827b85f237f02
font_01_sfnt_off00012ba8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12BA8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000143ba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x143BA 17544 bytes
SHA-256: 5ef8d5f93d87a4a6788274d372a7800347a4cb0863badb66353895de438e7c24