Malicious PDF — malware analysis report

Static analysis result for SHA-256 c9708d30d88535ad…

MALICIOUS

PDF

88.8 KB Created: 2021-06-24 04:09:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: 4fad5b409f147e69c9cd71e5fb3dd4af SHA-1: 042f47168830bc74c1ffd3ffe0ecb6e7b053a866 SHA-256: c9708d30d88535ad012d9a03b7b8862a59b3642ea2bd5351d3b9acbd087ba25e
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple compromised WordPress sites, indicating a phishing or redirection attempt. The ClamAV detection and ML classifier strongly suggest malicious intent. The document body is heavily obfuscated and contains metadata from wkhtmltopdf, but the primary malicious function appears to be the distribution of links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://3handseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a8438be5bd0---pajifilu.pdf In PDF document text
    • https://chocoinmobiliario.com/wp-content/plugins/super-forms/uploads/php/files/86d563db661e5b2b41a1761c0b62d04d/64565649444.pdfIn PDF document text
    • http://veronicanealhome.com/wp-content/plugins/formcraft/file-upload/server/content/files/2/1607920a599a81---91405781079.pdfIn PDF document text
    • https://egca.fr/userfiles/file/fiviludisasugilor.pdfIn PDF document text
    • http://alexandersorokolaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/sukojofulumasuwawifolux.pdfIn PDF document text
    • https://www.hungryalex.com/wp-content/plugins/super-forms/uploads/php/files/3fn47b1sbfqu78nrkekhtfreqq/torapilatuwojebivu.pdfIn PDF document text
    • https://doitsolutions.co/wp-content/plugins/super-forms/uploads/php/files/33aa0fb1db233725568b4c8e2be3d1f0/bavanilux.pdfIn PDF document text
    • http://nadiadsa.org/userfiles/file/xogitamiloverufanenugoko.pdfIn PDF document text
    • http://www.finanzanlagen-honorarberatung.de/wp-content/plugins/formcraft/file-upload/server/content/files/160836ed634178---31179468380.pdfIn PDF document text
    • http://colorfusion.us/admin/images/file/borepenuminuze.pdfIn PDF document text
    • https://mymovingestimate.com/wp-content/plugins/super-forms/uploads/php/files/99796f070355c0ea75859768888b3148/zisixowawasomedivi.pdfIn PDF document text
    • https://selectwifi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bc805580fb4---21245614883.pdfIn PDF document text
    • http://www.iece.in/userfiles/file/semasujumowided.pdfIn PDF document text
    • http://sarahscupcakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607161b011ad2---96927607525.pdfIn PDF document text
    • https://www.ideaklinik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16089ab5f51987---dexenuvibuzofilitozaf.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=concepto+de+heridas+pdfPDF 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://scripts.sil.org/OFLIn 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_off000108ee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108EE 5116 bytes
SHA-256: 15034b3fba152c16f9499a8b20b40647970e35e26e1c9a00dd1eb2d44639af3f
font_01_sfnt_off00011a4a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A4A 11740 bytes
SHA-256: 4ce9afd04361e56708469b3f4acc2bf3ffd57e1ab4afa005344c0ba36e69c9ac
font_02_sfnt_off00013fe5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13FE5 16060 bytes
SHA-256: 99ddc6f5858eb134f8024171ebe717cbd02485c31471b921a5021903b5272953