Malicious PDF — malware analysis report

Static analysis result for SHA-256 73a99f2a46cc18b4…

MALICIOUS

PDF

74.4 KB Created: 2021-09-18 11:55:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 49a54452fae7435788e46b837c82cfc6 SHA-1: 58ba61ebaad5279780e3cf711e820e9f4069b42b SHA-256: 73a99f2a46cc18b47d6e3e6e89456da8f78347773dfcd58426a8dfa635101b2d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware delivery. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

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 https://www.intermediastudios.com.mx/wp-content/plugins/super-forms/uploads/php/files/39b1d9b614dd481520db53e01efc03de/41904340733.pdf In PDF document text
    • https://wlao.on.ca/wp-content/plugins/super-forms/uploads/php/files/1c141527e1aa7d034a41d73163cc381f/sanolamimud.pdfIn PDF document text
    • https://netron.pt/app/webroot/media/files/21127721459.pdfIn PDF document text
    • http://zoscm.zohukum.com/ckfinder/userfiles/files/kibidusafogonax.pdfIn PDF document text
    • http://krupongs.com/images/file/tesakeziwowanugozonaxumul.pdfIn PDF document text
    • http://rebizplus.com/userfiles/file/watolasupes.pdfIn PDF document text
    • https://legend-chang.com/UserFiles/files/mulefofen.pdfIn PDF document text
    • http://sochi-vitrazhi.ru/ckfinder/userfiles/files/wedeto.pdfIn PDF document text
    • http://westernstudioservice.com/admin/userfiles/file/silupid.pdfIn PDF document text
    • http://www.theflightfest.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613add091be7b---supidekajufexuxaxeler.pdfIn PDF document text
    • https://bomberosdenavarra.com/userfiles_nexo/files/45636927218.pdfIn PDF document text
    • http://musicpark-live.de/userfiles/file/visoguzinul.pdfIn PDF document text
    • https://tuoitre.bacgiang.gov.vn/lib/ckfinder/files/kalapiz.pdfIn PDF document text
    • http://chataphan.com/file_media/file_image/file/zemutevigako.pdfIn PDF document text
    • http://www.kliningstroy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16130fd71e9c6f---97523883563.pdfIn PDF document text
    • http://xn--h1acbpobggs.xn--p1ai/data/files/nevuwufosegesese.pdfIn PDF document text
    • http://abwmercury.com/uploads/files/rawofuwiwomojeb.pdfIn PDF document text
    • https://mandalaconfeccao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16143026ea4f94---21934320940.pdfIn PDF document text
    • http://elektromig.pl/userfiles/file/647101602.pdfIn PDF document text
    • https://diedacorporation.net/freesiafiles/file/murarekosikasazeva.pdfIn PDF document text
    • http://tlxzkj.com/uploads/file/071420562533.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=official+mobdro+appPDF 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_off0000c037.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC037 10444 bytes
SHA-256: 082515257547e842f81b818e1e0d86cd6ea5c9b8008a22c17e79a21a2d25e555
font_01_sfnt_off0000d799.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD799 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000efab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFAB 17568 bytes
SHA-256: d71b12be69d6068dd3cc05cda1ec500500a1153154ae4819241f01bb85092623