Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf72e71088a941ba…

MALICIOUS

PDF

81.1 KB Created: 2021-09-19 09:31:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-22
MD5: f9dddcf29ec2ce6fce280c204de5fc7c SHA-1: 0bc0e7319bce989b93790ace48dc5fd7412fdc74 SHA-256: cf72e71088a941ba7866abb162536d4e93d351d801c3c7ee89b123718056b28f
146 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs and is flagged as a link farm on disposable hosting, indicating a phishing or malware distribution attempt. The presence of a malformed exploit stream and ML classification further supports malicious intent. Although no scripts were explicitly extracted, the PDF structure and embedded URIs suggest it's designed to redirect users to malicious sites, likely for further exploitation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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
  • Malformed active-content stream length medium PDF_MALFORMED_EXPLOIT_STREAM_LENGTH
    A PDF stream that carries active/exploit-looking content has a declared /Length that does not match the recovered stream body. Malformed stream boundaries and length mismatches are common parser-evasion/supporting evidence around Reader exploit streams.
  • 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 https://pixomot.ru/uplcv?utm_term=samsung+cloud+service+android PDF link annotation
    • http://china-miyaco.com/img/file/20219323583.pdfIn PDF document text
    • http://artetendasud.it/userfiles/files/mizazelup.pdfIn PDF document text
    • https://theloneranger.tv/clients/loneranger/ckfinder/userfiles/files/4862543758.pdfIn PDF document text
    • https://edgecs.com/documents/tevujub.pdfIn PDF document text
    • http://nghiencuuykhoa.com/uploads/userfiles/file/dodusukivafaradezezavis.pdfIn PDF document text
    • https://gsacademy.ge/uploads/files/kezomubuzuwegidal.pdfIn PDF document text
    • http://www.tractortools.cz/ckfinder/userfiles/files/bumamolokegipijakuneku.pdfIn PDF document text
    • https://habibitours.org/ckfinder/userfiles/files/23163027143.pdfIn PDF document text
    • https://volandovia.it/public/fileeditor/file/goxisusodibisopefuragosim.pdfIn PDF document text
    • http://mascotdd.com/file_media/file_image/file/lavami.pdfIn PDF document text
    • http://megatex-plast.ru/pub/file/4787081453.pdfIn PDF document text
    • https://www.akilciilacdernegi.com/ckfinder/userfiles/files/45295098859.pdfIn PDF document text
    • http://hidropro.hu/upload/zamasavesenafapal.pdfIn PDF document text
    • http://bigbulkbags.ahmadpackages.com/survey/userfiles/files/47585340364.pdfIn PDF document text
    • https://vietnamwelder.vn/uploads/news_file/takerobelupodugune.pdfIn PDF document text
    • http://seasonmediagroup.com/pic/file/ganusupezevejowibikuto.pdfIn PDF document text
    • https://eclipsetheaters.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612efa1405506---79007018553.pdfIn PDF document text
    • https://robustbrakes.com/administrator/imagetemp/file/timetakewima.pdfIn PDF document text
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/16144a26f4cdf9---vabatanimurakirenev.pdfIn PDF document text
    • http://www.anclupnapoli.it/userfiles/file/fakojedubufaketulenuk.pdfIn PDF document text
    • https://linhquan-group.com/upload/ck/files/8518012418.pdfIn PDF document text
    • http://medicalproduct.hu/images/files/96901609796.pdfIn PDF document text
    • http://avtrak.ru/ckfinder/userfiles/files/63456816871.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_off0000d9e1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9E1 17016 bytes
SHA-256: 5724c230237e3413cc0cb6deb806bce4aa29bbb40870444b814f93f0c8ff4d61
font_01_sfnt_off000105e6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105E6 10856 bytes
SHA-256: c52d3eb477ca8d82eacdbcf033519d3007b55a586c2c3dbb357a919d638ac404
font_02_sfnt_off00011eba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11EBA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1