Malicious PDF — malware analysis report

Static analysis result for SHA-256 c1f91a23fec81d3c…

MALICIOUS

PDF

83.1 KB Created: 2021-09-11 04:17:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 77c209068860fdeec7d3c035c8d469d6 SHA-1: b71ca1640aed4e9810d90a1b42a0021c5e49473e SHA-256: c1f91a23fec81d3c74ab494f5ff0c5db64d16d5d2491fd9e143fccd4eb5d1ebc
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by multiple heuristics as a link farm and a potential phishing or malware distribution vector. The ML classifier and ClamAV detection strongly indicate malicious intent. The embedded URLs, particularly those hosted on compromised CMS uploads, suggest an attempt to redirect users to malicious content. No scripts were extracted, but the overall structure points to a phishing or malware delivery attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://serendipityorlando.com/wp-content/plugins/formcraft/file-upload/server/content/files/161337f864ac2c---texoxe.pdf In PDF document text
    • http://www.tamtrebinhminh.com/public/files/vujidobalazulisesewosag.pdfIn PDF document text
    • http://tabouligrill.com/ckfinder/userfiles/files/wenix.pdfIn PDF document text
    • https://www.pferde-fuer-unsere-kinder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613bc7e9b7843---9319630825.pdfIn PDF document text
    • http://medizator.ru/ckfinder/userfiles/files/25594754606.pdfIn PDF document text
    • http://kqcme.yiaiwang.com.cn/upload/files/63744536321.pdfIn PDF document text
    • http://congseng.com/uploadfile/files/pedikixenorad.pdfIn PDF document text
    • http://tiszaladany.hu/upload/file/25707967347.pdfIn PDF document text
    • https://umiyawoodworks.com/fckdb/userfiles/file/xokasabarabiz.pdfIn PDF document text
    • http://tfe-design.dk/userfiles/file/12798611509.pdfIn PDF document text
    • https://www.truesdalepainting.com/wp-content/plugins/formcraft/file-upload/server/content/files/161306fb4a7896---59260336420.pdfIn PDF document text
    • http://langmypham.com/luutru/files/82368172695.pdfIn PDF document text
    • http://www.jindatunnel.com/up_files/file/getovudovajo.pdfIn PDF document text
    • http://maslatalaia.com/userfiles/file/87089314260.pdfIn PDF document text
    • https://massagetheory.ca/wp-content/plugins/super-forms/uploads/php/files/d992687dd2621ac8b07293a8cef90241/40184984567.pdfIn PDF document text
    • https://fullgame.hu/uploads/files/15691348402.pdfIn PDF document text
    • https://nbcmedia.vn/ckfinder/userfiles/files/20509796179.pdfIn PDF document text
    • https://sevenhillsgroup.net/ckfinder/userfiles/files/bujipoke.pdfIn PDF document text
    • http://chicopharm.com/upload/files/19832767850.pdfIn PDF document text
    • http://samtle.net/ckupload/files/zotisidorawirigi.pdfIn PDF document text
    • https://comobrew.com/newsite/images/user_uploads/file/vufeduzigoxepi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=fast+and+furious+7+full+movie+watch+online+free+englishPDF 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_off0000dd90.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD90 11204 bytes
SHA-256: 55ffceb7fd9d81c9733643214f48f70fdf3ce6a97d4325bc7b4ff1bee607cd2a
font_01_sfnt_off0000f782.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF782 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010f94.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F94 18128 bytes
SHA-256: 2687ec01e3a87444447264eb77007bdbeb77439aadc657e3056d902304c07380