Malicious PDF — malware analysis report

Static analysis result for SHA-256 16f2cff5c7269f2c…

MALICIOUS

PDF

83.5 KB Created: 2021-08-25 01:24:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: fc6936d66dee89e592074530eb0fed36 SHA-1: 221b046d3b95a4459ad8205cc1d2ef0a359649c1 SHA-256: 16f2cff5c7269f2c6714d5eb7fad897bacc3a4616f29ec12cbd235a9776039d7
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a link farm pointing to multiple unknown URLs, many hosted on compromised WordPress sites. ClamAV and ML classifiers flagged this PDF as malicious, likely due to its structure and the nature of the linked content. The primary attack pattern observed is the use of a link farm to direct users to potentially malicious or compromised external resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://az4group.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160bc0c633a431---17840191279.pdf In PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a16d84dd3e5---nevujo.pdfIn PDF document text
    • http://permianhighschool1970.com/clients/e/ef/efee9fcbc667252fc4b649c8163d3733/File/81828197198.pdfIn PDF document text
    • http://vigova.vn/Images_upload/files/jikokemaxegijuwoxelaso.pdfIn PDF document text
    • http://renovator.cz/files/file/92484067896.pdfIn PDF document text
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/b2ce1b7516a5701afa94165cca952343/kopelewo.pdfIn PDF document text
    • http://drvision.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607007ca5189e---toxikufizenas.pdfIn PDF document text
    • http://shuswapladystriders.ca/userfiles/file/24371272461.pdfIn PDF document text
    • http://www.badischer-kunstverein.de/ckfinder/userfiles/files/dovevevana.pdfIn PDF document text
    • http://akicgiyim.com/userfiles/file/gudativob.pdfIn PDF document text
    • http://brezov-gaj.si/uporabnik/file/sesojenojiso.pdfIn PDF document text
    • http://xn--h49al71atridzo.com/userData/board/file/14671826860.pdfIn PDF document text
    • http://inlovehuahin.com/file_media/file_image/file/dezalewek.pdfIn PDF document text
    • http://ziguratex.com/helpdesk/app/webroot/img/userfiles/files/46081642975.pdfIn PDF document text
    • http://remontnoedelo.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1609b9ec3f06f4---82421921111.pdfIn PDF document text
    • http://erbilsunhotel.com/wp-content/plugins/super-forms/uploads/php/files/eq0qpk20b01cphptdgvutfmvv5/9104390577.pdfIn PDF document text
    • https://lsp.od.ua/wp-content/plugins/super-forms/uploads/php/files/633i5gtlmp31lmucg1vpdd4gj1/bofiwetotusesaju.pdfIn PDF document text
    • http://teamtrinity.net/trinitya/file/71767201211.pdfIn PDF document text
    • http://www.thelawchamber.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d46d913509---9252873370.pdfIn PDF document text
    • https://gz-topstar.com/wp-content/plugins/super-forms/uploads/php/files/0da40719b1baee35a043e0e9c7813bd2/gujojigikibola.pdfIn PDF document text
    • http://dobrasekacka.cz/userfiles/file/2989475911.pdfIn PDF document text
    • http://www.optionassurance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1609ece85aa4c4---94952060191.pdfIn PDF document text
    • http://lorofilmes.com/Uploads/ckfinder/userfiles/files/bexamekofiro.pdfIn PDF document text
    • http://ebiocell.com/uploadfile/file///2021080122004131.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=i+just+called+to+say+i+love+you+mp3+free+downloadPDF 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_off0000e0d9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0D9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f8eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8EB 16928 bytes
SHA-256: 5f40d7cd0415418e3e692fb6d944153a03c35047f7ecef774599ec5ad5e48d2a
font_02_sfnt_off00012502.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12502 11400 bytes
SHA-256: 4024f925f59cd8985b1b70e546bfcf5015abbad3632315fde767c9d40c01c676