Malicious PDF — malware analysis report

Static analysis result for SHA-256 8b849364801e4f92…

MALICIOUS

PDF

76.4 KB Created: 2021-09-02 18:18:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 82ab01dca4f06de19e773ab1b6a751b6 SHA-1: 72917c5b1769d3c4ead243db17d90bc3925ed261 SHA-256: 8b849364801e4f926d6dd73da411540d48425cff7aa85e11d5912ea0eafdc4aa
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF document that contains numerous links to external websites, many of which are hosted on compromised WordPress sites or disposable domains. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a link farm designed for SEO manipulation, and the presence of 'utm_term' parameters suggests a phishing or malicious redirection scheme. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to redirect users to phishing pages or download further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9943

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://chcial.ru/uplcv?utm_term=bible+pdf+nlt PDF link annotation
    • https://teplitsyoptom.ru/wp-content/plugins/super-forms/uploads/php/files/f2fd2e4a8ba35866145d27065e66ee71/18055613442.pdfIn PDF document text
    • https://hopefor.today/wp-content/plugins/super-forms/uploads/php/files/01cf4c730c08d4d7439a4611f783e54c/xinedekiwixezololorugox.pdfIn PDF document text
    • https://expresstestingatl.com/wp-content/plugins/super-forms/uploads/php/files/610e844d0313392b6eda6fc129cb01aa/33789236879.pdfIn PDF document text
    • https://digireg.se/upload/gijegezu.pdfIn PDF document text
    • https://samarthanamparisara.org/apadmin/uploads/userfiles/files/73244270568.pdfIn PDF document text
    • http://henri-ruch.ch/doc_pub/file/80622021055.pdfIn PDF document text
    • http://peggylittlelawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/78058087864.pdfIn PDF document text
    • https://www.emma-solutions.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a80ffca16fd---mipudabenekaxozinerejexa.pdfIn PDF document text
    • http://www.neslihanonur.com/wp-content/plugins/super-forms/uploads/php/files/f04bc723a2982554c1d9bcf83252d40f/3541913271.pdfIn PDF document text
    • http://sarahscupcakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a878535732---fedokowesakak.pdfIn PDF document text
    • http://mouaumfb.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609837bac9a38---ruwar.pdfIn PDF document text
    • https://deltagroup.bg/uploads/file/10254858774.pdfIn PDF document text
    • https://www.darrellstuckey.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ae6215c5603---mizaw.pdfIn PDF document text
    • https://amd-export.com/site/upload/file/85973674149.pdfIn PDF document text
    • https://vieclambanhang247.com/upload/files/98877044407.pdfIn PDF document text
    • https://geya99.com/ckfinder/userfiles/files/vonujomer.pdfIn PDF document text
    • https://www.mclarenpress.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c18496a98a1---5986536612.pdfIn PDF document text
    • http://klubalfa.org/img/userfiles/file/40985471646.pdfIn PDF document text
    • https://wrd13.com/force/file/fejulufalikopep.pdfIn PDF document text
    • http://dungcumaymoc.com/Images_upload/files/bafawimiji.pdfIn PDF document text
    • http://yuli-china.ru/d/files/bawejunixomejukakubigoz.pdfIn PDF document text
    • http://www.airportlimofortlauderdale.net/wp-content/plugins/formcraft/file-upload/server/content/files/160c1b89703293---2853749287.pdfIn PDF document text
    • http://miyozenemeryville.com/uploads/files/malil.pdfIn PDF document text
    • http://indiebookoftheday.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ec92d3da5f---31979457518.pdfIn PDF document text
    • http://jn-zhsc.com/upload/mokolijudorazefabop.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_off0000c7ed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC7ED 10136 bytes
SHA-256: 3f98398e94e6f04a5bc9f4968eb4a20b1ca0fb90ebb95cc0026a4b63dac67572
font_01_sfnt_off0000de62.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE62 17664 bytes
SHA-256: bc84d6ba9f4e7d5b1e0b56c38667c280a47ab170507b2a26682dae0b97e3c395
font_02_sfnt_off00010c52.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C52 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1