Malicious PDF — malware analysis report

Static analysis result for SHA-256 ecf9add112e208db…

MALICIOUS

PDF

68.0 KB Created: 2021-09-29 04:43:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 78f5001ce9486b08fec8d5f558041b21 SHA-1: 61bf223177dd8945d43900b12bf1c360af14821e SHA-256: ecf9add112e208db8739be94aef5dd914913c9bd2da4777b194e14e14a8553f9
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs and is flagged as a link farm, indicating a phishing or redirection attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with common phishing lures, potentially leveraging embedded JavaScript for malicious actions.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9957

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • 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://gzcaifeilai.com/ckfinder/userfiles/files/202109010803067231.pdf In PDF document text
    • https://vcubusinesssolutions.com/userfiles/file/9172651910.pdfIn PDF document text
    • http://msmzizkov.cz/data/dokumenty/38095212324.pdfIn PDF document text
    • https://www.info-service.com.tw/plugin/ckeditor/ckfinder/userfiles/files/26243129523.pdfIn PDF document text
    • http://manpukulivermore.com/uploads/files/78824737490.pdfIn PDF document text
    • https://iskoruma.com/upload/ckfinder/files/mozemuderepelunozedev.pdfIn PDF document text
    • http://innova-perila.ru/upload/files/juteg.pdfIn PDF document text
    • http://hwayoung.kr/upfile/files/gikonatuver.pdfIn PDF document text
    • http://www.tomasjelinek.com/img/pub/file/jefimowi.pdfIn PDF document text
    • https://malabarmail.com/ckfinder/userfiles/files/87216396104.pdfIn PDF document text
    • http://daiichigroup.net/uploads/news_file/vubenaro.pdfIn PDF document text
    • http://iknow.pl/files/file/39020744011.pdfIn PDF document text
    • https://prawobrzeze.info/userfiles/file/xabesumadux.pdfIn PDF document text
    • http://sushigonewildtogo.com/uploads/files/4050117102.pdfIn PDF document text
    • http://osayit.com/images/file/51566649084.pdfIn PDF document text
    • http://jiuxingchaoshi.com/uploads/file/091436089019.pdfIn PDF document text
    • http://studiospazioambiente.it/userfiles/files/9436127809.pdfIn PDF document text
    • https://villamishkan.com/310renonew/front/images/files/bubivinofodemubopijozenud.pdfIn PDF document text
    • http://prime-standard.com/piceditor/file/bologosax.pdfIn PDF document text
    • http://knowleangling.co.uk/ckfinder/userfiles/files/vufesinidadideza.pdfIn PDF document text
    • https://granitabrasive.hu/editor_up/52823403037.pdfIn PDF document text
    • https://bf-pomosch.ru/wp-content/plugins/super-forms/uploads/php/files/jc16m31fvfuv1lecjs2apb3sl6/nuvupunosu.pdfIn PDF document text
    • http://sp2wronki.pl/fotki/fotki/file/80960270588.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=apk+pubg+mobile+korea+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_off0000ad04.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAD04 14796 bytes
SHA-256: ae242a9bb435909e20ad1f37b95439d45ce0376fbe9ee98c579f2fca86374f4e
font_01_sfnt_off0000d222.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD222 10868 bytes
SHA-256: 0912a231c760947f335baa1ae3e8903750144b96da7f3fcfdf223ef27aa6e2c1
font_02_sfnt_off0000eac8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEAC8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1