Malicious PDF — malware analysis report

Static analysis result for SHA-256 8e47fa455d2d0635…

MALICIOUS

PDF

71.6 KB Created: 2021-09-22 11:30:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 21c5fc13067d927bdb2fa5a06bccfab1 SHA-1: 2eebd29be79db12d3201cf4ca4610e55751fe688 SHA-256: 8e47fa455d2d0635515ab30db8288ed9a38e98a6777a43d98ba0fe22cd8ddf6d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous embedded URLs, many of which point to disposable hosting or compromised WordPress sites, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to deliver second-stage payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9986

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://infrive.ru/uplcv?utm_term=science+class+7+textbook+pdf PDF link annotation
    • http://transdeliveris.lt/userfiles/file/98932484019.pdfIn PDF document text
    • http://sochi-polyana.com/ckfinder/userfiles/files/94764813296.pdfIn PDF document text
    • https://gkatsov.com/userfiles/file/61420068600.pdfIn PDF document text
    • http://permanentnimakeup-brno.cz/userfiles/files/kadivefed.pdfIn PDF document text
    • http://brandiassociati.it/userfiles/file/52278765573.pdfIn PDF document text
    • https://ncfouting.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f4fbd55716---norenitolikegox.pdfIn PDF document text
    • http://hndgyl.com/v15/Upload/file/202198124847781.pdfIn PDF document text
    • http://www.neoneophytou.com/ckfinder/userfiles/files/fudisekix.pdfIn PDF document text
    • http://oasis-inwaste.asia/files/file/mamedujav.pdfIn PDF document text
    • http://www.liveartsaskatchewan.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614101a947c9c---87562187241.pdfIn PDF document text
    • https://www.medicalbi.com/ckfinder/userfiles/files/kepuxebiwur.pdfIn PDF document text
    • http://chiangmai-esc.net/user_img/files/24057973583.pdfIn PDF document text
    • https://fenixfalt.com/userfiles/file/23191843541.pdfIn PDF document text
    • https://doublehair.center/upload/ckfinder/files/39779513221.pdfIn PDF document text
    • http://lnaixi.com/userfiles/file/20210917080817_540841802.pdfIn PDF document text
    • https://la-klamm.org/Files/files/vubisogakuton.pdfIn PDF document text
    • https://motoralbini.it/files/file/rivigopivubesefoni.pdfIn PDF document text
    • http://anoh.net/pds/userfiles/files/15471629580.pdfIn PDF document text
    • https://ctsgroups.asia/images/file/jufujivopawigelifipedusu.pdfIn PDF document text
    • http://mabo-meccanica.eu/userfiles/files/46824250030.pdfIn PDF document text
    • http://a-range.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1613e8a6d8c79e---15972403869.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_off0000b6ab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB6AB 15972 bytes
SHA-256: 69c62fbcfe328960078ad83932886de91da7d412430f3380a6fd552256522cf4
font_01_sfnt_off0000df34.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF34 10972 bytes
SHA-256: 4025c5cc9a4700807aa9172013ed29709251aebacc4314b665f9c24ba57bdc1c
font_02_sfnt_off0000f8a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8A3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1