Malicious PDF — malware analysis report

Static analysis result for SHA-256 258499f234757955…

MALICIOUS

PDF

83.2 KB Created: 2021-09-18 04:59:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 68d3acf4f6525cd61929afb1fa8aace5 SHA-1: dc1c0254c62f6ebf59679b4f4fb7c9a5ac4407fd SHA-256: 258499f234757955fa428db5a751e85824a16eff43fb9040fbf4662aed25548d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple external URLs, some hosted on compromised CMS uploads or disposable domains. The embedded URLs suggest an attempt to redirect users to malicious content or phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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://vanillasky-ch.com/images/files/78196123304.pdf In PDF document text
    • https://speeddating.lt/speeddating/ckfinder/userfiles/files/32303542352.pdfIn PDF document text
    • http://zonweringbelgie.nl/ckfinder/userfiles/files/80808823286.pdfIn PDF document text
    • http://g-shocktou.com/user_file/file/19537335908.pdfIn PDF document text
    • https://deesudcoolingtower.com/userfiles/file/solozopobopejuge.pdfIn PDF document text
    • http://phannhan.vn/files/usersfiles/files/60894849964.pdfIn PDF document text
    • https://dentalrud.com/userfiles/file/jogazarasotagalidomupeku.pdfIn PDF document text
    • https://mimpishio1bet.net/contents/files/vibevulabovajabefabep.pdfIn PDF document text
    • https://www.davidcosz.de/wp-content/plugins/super-forms/uploads/php/files/fntk4iruht41r4ie9qusdbcrli/75389455952.pdfIn PDF document text
    • http://abwingscolley.com/uploads/files/80781827706.pdfIn PDF document text
    • http://tribo.kz/userfiles/File/robegele.pdfIn PDF document text
    • http://xaydunganphubacninh.com/webroot/img/files/88737084104.pdfIn PDF document text
    • https://booburger.myagenda.cz/pictures/editor/files/sutifufaxojuvonodadov.pdfIn PDF document text
    • https://tumujerrusa.com/userfiles/gopowovugus.pdfIn PDF document text
    • http://elateridae.com/images/FCKeditor/file/30695524975.pdfIn PDF document text
    • https://ruta.hu/ckfinder/userfiles/files/jakelul.pdfIn PDF document text
    • http://uat.ideadunes.com/projects/ideadunes-portfolio-site/wp-content/plugins/formcraft/file-upload/server/content/files/161451bf179d36---7853827329.pdfIn PDF document text
    • http://www.luminicaambiental.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614127c54e416---15468647166.pdfIn PDF document text
    • http://ingpiazza.eu/userfiles/files/kigafuvide.pdfIn PDF document text
    • https://bisnismedsos.com/userfiles/file/93552672377.pdfIn PDF document text
    • http://structurecreative.com/wp-content/plugins/formcraft/file-upload/server/content/files/161405c4fa8145---jitomobutumeditebojekal.pdfIn PDF document text
    • http://bibrka-school.org.ua/ckfinder/userfiles/files/mamugerapumutaj.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=alexa+app+gratisPDF 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_off0000dce2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCE2 19556 bytes
SHA-256: a09b7cbeffab46ec333d5f9bb2cb2adca24620f92cd5bbdb66bc0ad558bcc12d
font_01_sfnt_off00010f41.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F41 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012758.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12758 10284 bytes
SHA-256: 713c0ea3e7039bf1b639b54b6c0c6e5db5eec4a34d28570a7507fa6243f847a3