Malicious PDF — malware analysis report

Static analysis result for SHA-256 811909fbf211f891…

MALICIOUS

PDF

84.7 KB Created: 2021-09-04 18:01:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 8e639512b4075142c85b9d0d225de190 SHA-1: 0d3cb2e405d350aa018ab8d45eb0befc78456285 SHA-256: 811909fbf211f891b07919788d8cfa3d65dc4fe7a4df8d029d360bc3f55d1613
196 Risk Score

Malware Insights

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

The sample is a PDF file that uses social engineering to prompt the user to install a browser extension or update, a common lure for malware delivery. The ML classifier and ClamAV detection strongly indicate malicious intent. The numerous embedded URLs suggest a link farm designed to host or redirect to malicious payloads, potentially leveraging compromised CMS uploads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Browser extension / update installation lure high SE_BROWSER_INSTALL_LURE
    Document tells the user to install a browser extension, plugin, viewer, or browser update to view content — a common social-engineering path for credential theft and malware installation
  • 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://medvor.ru/uplcv?utm_term=microsoft+word+to+pdf+file+converter+free+download PDF link annotation
    • http://777mto.info/contents//files/56756152328.pdfIn PDF document text
    • http://bazatalty.pl/wp-content/plugins/super-forms/uploads/php/files/b2b256c9b0be214fd75dd214c84b86de/6947316516.pdfIn PDF document text
    • https://fotojursa.cz/userfiles/file/9412860609.pdfIn PDF document text
    • http://firegallery.ru/img/upload/nitupajipafalugide.pdfIn PDF document text
    • https://cargobull.cz/res/file/kavako.pdfIn PDF document text
    • http://estatepie.com/files/userfiles/file/dizavimavatofaganowux.pdfIn PDF document text
    • http://bachova-terapia.sk/images/file/gofudugiguderunijutesaze.pdfIn PDF document text
    • https://ka-base.no/images_content/file/95819715436.pdfIn PDF document text
    • https://optical-axis.com/uploads/files/202109012349468727.pdfIn PDF document text
    • http://ski-experience-japan.com/images/blog//file/9845747686.pdfIn PDF document text
    • http://rucodelniza.ru/userfiles/file/vojukumapemunewusejakiki.pdfIn PDF document text
    • http://laiyi-art.com/userfiles/file/davetitisidax.pdfIn PDF document text
    • http://polish-house.com/uploades/fckeditorfile/wozilakoluxive.pdfIn PDF document text
    • http://jamoncup.es/wp-content/plugins/formcraft/file-upload/server/content/files/160ce233b2209d---97165986264.pdfIn PDF document text
    • https://diarch.in/WYSIWYGImage/file/mivivaxij.pdfIn PDF document text
    • http://siciny.eu/userfiles/file/76470634211.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608cf6eb8b2e3---22494860323.pdfIn PDF document text
    • http://princeworldwide.com/multimedia/userfiles/file/81805334124.pdfIn PDF document text
    • http://sazjah.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b6deca410e6---dakizevibajetoja.pdfIn PDF document text
    • https://benqmusicworkshop.com/fupload/file/vewakojafetimoxuzar.pdfIn PDF document text
    • http://hf1968.com/clients/48820/File/batonuporolomoxapiteri.pdfIn PDF document text
    • http://seksdagen.nl/userfiles/file/bumorile.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_off0000e6de.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6DE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fef0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFEF0 17420 bytes
SHA-256: 594de5d8b593050db6120239901b6697e041b388e34ea288951ae0b1bf03accd
font_02_sfnt_off00012c46.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C46 10760 bytes
SHA-256: 34284cf300c3d4a5f9a44980990a0f742070031575aefc6b873533b4ee0c46ed

Open this report in the interactive analyzer, or submit your own file for analysis.