Malicious PDF — malware analysis report

Static analysis result for SHA-256 dcd7a23d4a86b87a…

MALICIOUS

PDF

78.2 KB Created: 2021-09-19 12:14:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 453bfdf01aeff8ec12521b43c1558313 SHA-1: 7d51f901c85fd5591f1008b829c50ea449bf43a6 SHA-256: dcd7a23d4a86b87a0d9cc430f0fe143a10e3cfc4e06a1e7ea3862abf79af4dfa
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was identified as malicious by a machine learning classifier and ClamAV. It contains a link farm with numerous URLs pointing to potentially compromised websites or disposable hosting, indicating an attempt to redirect users to malicious content. The presence of PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics further supports this. No scripts were extracted, but the structure suggests a phishing or malware distribution lure.

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 http://www.saveurspoitoucharentes.com/admin/ckfinder/userfiles/files/lazax.pdf In PDF document text
    • http://stfurnimart.com/file_media/file_image/file/6500107287.pdfIn PDF document text
    • http://diagonal.org.ar/wp-content/plugins/formcraft/file-upload/server/content/files/16133281050078---92129796480.pdfIn PDF document text
    • http://pincailight.com/zk/UploadFile/file/2021091907112073499.pdfIn PDF document text
    • http://www.psychophonie-tarbes.com/ckfinder/userfiles/files/rodun.pdfIn PDF document text
    • http://golfproradost.cz/webpagebuilder/ckfinder/userfiles/files/rizipavoze.pdfIn PDF document text
    • https://brokenspoke.com/wp-content/plugins/super-forms/uploads/php/files/605c8834de08fc0a3995dc50054c1da1/pexasogikowenetotiwenupi.pdfIn PDF document text
    • https://www.tristar-technology.com/ckfinder/userfiles/files/xetabajorakuvaputizuxot.pdfIn PDF document text
    • http://cl-metalparts.com/d/files/59305720054.pdfIn PDF document text
    • https://sesconbs.org.br/ckfinder/userfiles/files/72935147902.pdfIn PDF document text
    • https://mangalargalux.com.br/ckfinder/userfiles/files/24595004345.pdfIn PDF document text
    • http://laulumaja.fi/ckfinder/userfiles/files/sigiroremipa.pdfIn PDF document text
    • http://gaushalango.com/uploaded_files/userfiles/files/88294041738.pdfIn PDF document text
    • http://mobilahomedesign.com/userfiles/files/lajoresuvasarofoxup.pdfIn PDF document text
    • http://4998horo.gmmwireless.com/contents/files/88804636099.pdfIn PDF document text
    • https://www.indee-r.fr/wp-content/plugins/super-forms/uploads/php/files/219ff57ed40206816de8a1b48a1454a4/86556460729.pdfIn PDF document text
    • https://mar3ol.com/Files/files/bowokakegopusasibajotera.pdfIn PDF document text
    • https://pro-biomed.com/admin/userfiles/file/87108075319.pdfIn PDF document text
    • http://chia4kids.ru/ckfinder/userfiles/files/miwupekavujunikamakob.pdfIn PDF document text
    • http://texmet.pl/userimages/file/96798503053.pdfIn PDF document text
    • https://butterfly-propertymanagement.com/userfiles/file/29439148264.pdfIn PDF document text
    • https://rubenoferro.com/userfiles/file/xipimulefijafow.pdfIn PDF document text
    • https://sts-cct.com/app/webroot/userfiles/files/wozokiruzoge.pdfIn PDF document text
    • http://elcampoeco.org/FCKeditor/file/56862780689.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=dropbox+sync+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_off0000cf2b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF2B 17024 bytes
SHA-256: 7758a674cb4f706f38f22ce8f5ed65a7f8d8cf88b8065a99dd8dffdff79edc91
font_01_sfnt_off0000fb93.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB93 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000113aa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x113AA 10588 bytes
SHA-256: 5d093283d9c954c363a7c741dd0e4b6eabdb652d0f7cb42de0c12bb70442961b