Malicious PDF — malware analysis report

Static analysis result for SHA-256 a64a65f79451be9b…

MALICIOUS

PDF

85.4 KB Created: 2021-06-23 14:19:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-07
MD5: c0de96611cd2c1c2727529c4f2bf46d6 SHA-1: 4f960ddd31c1e38f2731b8329257128199f203ef SHA-256: a64a65f79451be9b465a8c6e3e08c27d6276515f34a317e46d4a9c814c4e35f2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file contains numerous embedded URLs, many of which point to compromised WordPress sites utilizing formcraft plugins for file uploads. The ML classifier and ClamAV detection strongly indicate malicious intent. The document body, though heavily obfuscated, contains text related to 'Bacterias en alimentos' and metadata from wkhtmltopdf, suggesting it was generated programmatically to host a collection of links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.tai.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160b82a03ae523---nawuj.pdf In PDF document text
    • https://mygoaltv.com/ipp/images/uploads/files/fojigejovozuwo.pdfIn PDF document text
    • https://www.audioclinica.pt/wp-content/plugins/super-forms/uploads/php/files/u5qtk5hc8bf3sleqv4iaq5sntl/78830902116.pdfIn PDF document text
    • http://zelene-centrum.cz/webpagebuilder/ckfinder/userfiles/files/momavogasozage.pdfIn PDF document text
    • https://bjsteelvietnam.com/upload/fck/file/bexifolutawugurukobom.pdfIn PDF document text
    • http://www.rebranded.tv/wp-content/plugins/formcraft/file-upload/server/content/files/16097afc8bf669---3657597797.pdfIn PDF document text
    • https://endoaccessories.com/wp-content/plugins/super-forms/uploads/php/files/dk44aod5mlucp48sc24ijld1g7/tinosubabivofurelumezadax.pdfIn PDF document text
    • https://www.medipratik.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072e50ee3d7c---dezepanumapokaw.pdfIn PDF document text
    • https://avenirpourtous.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1606f5f91c511d---xabifadidoxawavitaj.pdfIn PDF document text
    • https://ctsgroups.asia/images/file/ratujopimabepesof.pdfIn PDF document text
    • https://rhdplumbing.com/wp-content/plugins/super-forms/uploads/php/files/54575aa319468dec430081e0a413305d/40930427791.pdfIn PDF document text
    • https://webmodeli.com/wp-content/plugins/formcraft/file-upload/server/content/files/160796d4ed66a0---77155632374.pdfIn PDF document text
    • http://ibb-online.ru/f/file/virib.pdfIn PDF document text
    • https://finances-canada.com/wp-content/plugins/super-forms/uploads/php/files/25afe8c10bad2012a468c2865cedf2ac/wuwujalogopemowa.pdfIn PDF document text
    • https://foodsafetytrainingcertificaIn 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/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=bacterias+en+alimentosPDF 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_off0000fa04.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA04 4996 bytes
SHA-256: 7cd6b4138307c52d2917b3592bd8b04ac22e50ca13faa6a1d864f73008a47733
font_01_sfnt_off00010ae7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10AE7 13216 bytes
SHA-256: 0c66932af4d5d6c50c12e1ddb6e70693b2e2c882cab63b1e2ceb6a903cb3de74
font_02_sfnt_off0001344e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1344E 16060 bytes
SHA-256: d1a84ba8f0e4a827a048d387db8dd5dae3538f1c7e72415b16af587a9947cdc7