Malicious PDF — malware analysis report

Static analysis result for SHA-256 84025c2afa91821e…

MALICIOUS

PDF

82.2 KB Created: 2021-09-19 14:55:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 671e3ea6dddf64cd337a3ed71e67bdd3 SHA-1: 45a182d7544ba653ad544dee258f4457dc59bb0c SHA-256: 84025c2afa91821edd6ee3d82bc2f07e209a57011b9fa139e8a4ab55f3d2c702
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised websites or are structured as link farms. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or directing users to malicious content. The presence of external URI heuristics and link farm indicators supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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 http://jungvassar.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/11686422630.pdf In PDF document text
    • http://ecohort.com/userfiles/files/49779351439.pdfIn PDF document text
    • http://www.mostex.sk/files/articles/file/xexare.pdfIn PDF document text
    • http://phunggia.biz/userfiles/file/tazudeweko.pdfIn PDF document text
    • http://hengtaixin.com/HangShun/ckfinder/userfiles/files/rizibaliwule.pdfIn PDF document text
    • http://hidropro.hu/upload/14066603073.pdfIn PDF document text
    • http://www.juniorcollege.cl/ckfinder/userfiles/files/fivugopumujelovelupa.pdfIn PDF document text
    • https://gitedu.in/ckfinder/userfiles/files/19430187895.pdfIn PDF document text
    • http://ordineveterinarireggioemilia.it/userfiles/files/20504146025.pdfIn PDF document text
    • http://heldermusic.nl/ckfinder/userfiles/files/66351322399.pdfIn PDF document text
    • http://novaserv.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139f7802cd4b---37439825666.pdfIn PDF document text
    • http://velapower.com/glwh/UploadFile/file/2021090903030073499.pdfIn PDF document text
    • https://makemycake.gr/wp-content/plugins/super-forms/uploads/php/files/urg2899l5pkf9gdq7ql91mjqkp/zetog.pdfIn PDF document text
    • http://pusancard.com/userData/board/file/kunemememimunolebesixixip.pdfIn PDF document text
    • https://gedayapi.com/userfiles/file/xukajepefufazivulovuxa.pdfIn PDF document text
    • https://kamhosting.nl/ckfinder/userfiles/files/wimobejokotux.pdfIn PDF document text
    • http://abwnickersonplaza.com/uploads/files/zasopekasazular.pdfIn PDF document text
    • https://balaji-technology.com/userfiles/file/jevajevonefuxasibefute.pdfIn PDF document text
    • http://gsoam.ge/wp-content/plugins/formcraft/file-upload/server/content/files/1614709a406329---rufenawoneziwot.pdfIn PDF document text
    • https://postele-z-masivu.sk/ckfinder/userfiles/files/90733385363.pdfIn PDF document text
    • http://kaitosushisb.com/uploads/files/46666246550.pdfIn PDF document text
    • https://groupunsur4.com/contents/files/pekufobasebexuketasagu.pdfIn PDF document text
    • https://www.3dreamchurch.com/wp-content/plugins/super-forms/uploads/php/files/2aee5e5e0f71b6534f98a92ce908ab12/17254792473.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=livenet+tv+ad+freePDF 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_off0000deb8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDEB8 10036 bytes
SHA-256: ab2ec5325e8650579eb4dbbef8b27ca6dfc85621dfa2ec1bb22a2a2855b93b6a
font_01_sfnt_off0000f51c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF51C 17700 bytes
SHA-256: acd0b8e48145e35ba63b09296841263a227a4f0973b53408f46293a239823168
font_02_sfnt_off00012341.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12341 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1