Malicious PDF — malware analysis report

Static analysis result for SHA-256 6a4a181af9a854eb…

MALICIOUS

PDF

80.5 KB Created: 2021-09-19 17:16:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 10b068810a56824f1be45abab5da933d SHA-1: 500e142fb80e1f166901819a3e3c96f3edc65168 SHA-256: 6a4a181af9a854eb42ca76f3dca2221b8e8b14defe17e1077897552bffc3a1ec
96 Risk Score

Malware Insights

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

The PDF contains a link farm with numerous URLs, many hosted on compromised or disposable domains, indicating a malicious intent to redirect users. The ML classifier strongly flagged this PDF as malicious, supporting the assessment of a phishing or malware distribution attempt. No scripts were extracted, but the structure and URL patterns are consistent with a malicious document designed to lure victims.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

Heuristics 5

  • 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://pre-www.bridge-college.com/uploaded/ckeditor/files/57336926890.pdf In PDF document text
    • https://pontus-sd.eu/uploads/file/nufukune.pdfIn PDF document text
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/869861f9796b7e1ef677d29dd49e03f2/lezaxanewigorib.pdfIn PDF document text
    • http://christopherspubandgrille.com/userfiles/files/36070755598.pdfIn PDF document text
    • https://bandotrading.com/uploads/file/36008122034.pdfIn PDF document text
    • http://www.optimizecost.com/admin/ficheros_fckedit_subidos/gisosulimebore.pdfIn PDF document text
    • https://www.wsbe17hongkong.hk/_bin/ckfinder/userfiles/files/40727045716.pdfIn PDF document text
    • https://gotoko.com/cmsv2/upload/files/powosivilodijigisi.pdfIn PDF document text
    • http://www.feniuniversity.edu.bd/app/webroot/ckfinder/userfiles/files/kasunowajenesujamarika.pdfIn PDF document text
    • http://gz-chengeng.com/uploadfile/files/pigoxafofemepubok.pdfIn PDF document text
    • http://influences-vegetales.eu/assets/Image/files/7787605988.pdfIn PDF document text
    • http://ptichile.cl/userfiles/file/nokebabimaremarotewu.pdfIn PDF document text
    • http://fleshlight-tw.com/userfiles/file/39395301911.pdfIn PDF document text
    • http://powercleanperu.com/cms_powerclean_2015/sgi_userfiles/userfiles/files/xunapawamagi.pdfIn PDF document text
    • https://ateliersmq.com/pevron/www/img/file/13084356484.pdfIn PDF document text
    • https://pasarangroup2.com/contents/files/58367901314.pdfIn PDF document text
    • http://www.deadclan.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613a83b6dfd1d---24534245849.pdfIn PDF document text
    • https://phase1acoustics.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a18a036df5---64679411079.pdfIn PDF document text
    • https://khanikango.in/file/16618949936.pdfIn PDF document text
    • http://yunnanyingxiang.com/ckfinder/userfiles/files/3746627688.pdfIn PDF document text
    • http://location-appartement-venise.com/italie_documents/files/43318710580.pdfIn PDF document text
    • https://artistaone.co/userfiles/files/zoronutixexinixorekaboxa.pdfIn PDF document text
    • http://aktifbant.com/resimler/files/94137024457.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=does+instagram+tell+you+when+someone+views+your+profilePDF 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_off0000d2be.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD2BE 11172 bytes
SHA-256: bc0eb16704078dcd2ef8fae873a243aeedf9cb4cc4ca9c4b1acf966880ed0c38
font_01_sfnt_off0000ecc3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECC3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000104d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104D5 18316 bytes
SHA-256: c889c96c9d5b2e30e289a0956f1bd99c0d77259cc139207c9ed930e7a19ed3dd