Malicious PDF — malware analysis report

Static analysis result for SHA-256 f664044feb00ffc4…

MALICIOUS

PDF

80.8 KB Created: 2021-09-17 18:18:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: a1d62c8221b55be1ea74b78407691436 SHA-1: 26f6cf7707a0023be01f6cd2af6f5c47c70df053 SHA-256: f664044feb00ffc4e68dea730354dc7d9e8d47640770b4ec3f86223d3afa81b1
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and multiple external URIs, including one pointing to a suspicious domain ('synerhu.ru') with a 'utm_term' parameter, suggesting a phishing or tracking lure. The ML classifier and ClamAV detection strongly indicate malicious intent. The presence of embedded JavaScript, while not directly executed by the PDF reader itself, is often used in conjunction with exploits or to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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 https://synerhu.ru/uplcv?utm_term=tottenham+live+free PDF link annotation
    • http://mikllc.mn/uploads/files/dukixokelef.pdfIn PDF document text
    • https://honkakuji.jp/honkakuji/images/ckfinder/files/79643448519.pdfIn PDF document text
    • http://www.sosonomo.com/ckfinder/userfiles/files/wotatonowuguwidimube.pdfIn PDF document text
    • http://studiotipaldo.com/userfiles/files/82357686843.pdfIn PDF document text
    • https://www.horisunmauritius.com/wp-content/plugins/super-forms/uploads/php/files/bfd22297dc6b69dc7d17959c7e5a84f3/48243123110.pdfIn PDF document text
    • https://ag-concept.ru/wp-content/plugins/super-forms/uploads/php/files/14c274aa5e2373fa80a3a2ddd73a2f62/66118220074.pdfIn PDF document text
    • http://autosoftware.company/autoresponders_images/files/56087849161.pdfIn PDF document text
    • http://net-work.cz/data/file/65138521468.pdfIn PDF document text
    • https://niboparis.com/upload/fckeditor/file/1630889204_1.pdfIn PDF document text
    • https://smilaxlabs.com/userfiles/files/fivolakajovevaradeg.pdfIn PDF document text
    • https://pchome.uzai.ca/upload/files/kesekemupusawunef.pdfIn PDF document text
    • http://barsugo.com/ckfinder/userfiles/files/tekaxinize.pdfIn PDF document text
    • https://landbar.com/app/webroot/js/ckfinder/core/connector/upload/files/68946992965.pdfIn PDF document text
    • http://www.atccs3.it/atccs3/fckeditor/editor/ckfinder/userfiles/files/voxurusabafukizijevisusu.pdfIn PDF document text
    • http://xn--42-jlclgg6a3e.xn--p1ai/userfiles/file/50527914395.pdfIn PDF document text
    • http://prakseologia.eu/userfiles/file/59520017186.pdfIn PDF document text
    • http://thietkewebsite.btccorp.vn/uploads/files/roxaganexi.pdfIn PDF document text
    • https://gimenezricarte-deltabogados.com/ckfinder/userfiles/files/40203438834.pdfIn PDF document text
    • http://muabannhagiare.net/images/uploads/files/12754814697.pdfIn PDF document text
    • http://cuspsurgeons.com/userfiles/file/22111916674.pdfIn PDF document text
    • http://chaodontuonglai.vn/uploads/ck_upload/files/xixemofojebus.pdfIn PDF document text
    • http://www.guus.edu.mn/ckfinder/userfiles/files/giwumobexekaki.pdfIn PDF document text
    • https://kaowei.tw/image/files/20210909_035321.pdfIn PDF document text
    • http://www.miyadenthai.com/image/upload/File/49308956839.pdfIn PDF document text
    • 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_off0000d491.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD491 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000eca8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECA8 10340 bytes
SHA-256: de4defbe02e1e433967f32a6db55c5bcca574f114d0d2a40d081db1a802906c2
font_02_sfnt_off000103bc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103BC 18976 bytes
SHA-256: 0faf63758be70e132b05f3bf72c4f7ecf4db3855f2776463272f07aec7fd2825