Malicious PDF — malware analysis report

Static analysis result for SHA-256 16c9b71c49287683…

MALICIOUS

PDF

146.1 KB Created: 2021-10-06 19:01:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 39a4f7752e5d7804bddfbddf8a24aa23 SHA-1: 0233f077a31db885c50a569c30c3ce35e3546ea4 SHA-256: 16c9b71c492876830f96f3dfa8d694dd3f6210ef66add8c19efe336e7be6a3a2
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm designed to redirect users to malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9913

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
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://pistant.ru/uplcv?utm_term=how+to+spawn+wall+of+flesh+in+terraria PDF link annotation
    • https://dubaimotorcycletours.com/uploaded_images/files/46834719885.pdfIn PDF document text
    • https://greenlakecruises.com/ckfinder/userfiles/files/bavajododurifudiguku.pdfIn PDF document text
    • http://amsuatrust.org/survey/userfiles/files/83303566479.pdfIn PDF document text
    • https://www.acta-mobilier.fr/ckfinder/userfiles/files/vifojunaxive.pdfIn PDF document text
    • http://boracayg.com/FileData/ckfinder/files/20211003_204A46685B0E4B78.pdfIn PDF document text
    • https://corumosmanlimakina.com/js/ckfinder/userfiles/files/kumofinikutej.pdfIn PDF document text
    • http://structurecreative.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f260d7e46f---55760475684.pdfIn PDF document text
    • http://pappteam.hu/userfiles/file/38937206620.pdfIn PDF document text
    • http://www.naturapreserved.com/wp-content/plugins/formcraft/file-upload/server/content/files/161381e7ff0617---311953558.pdfIn PDF document text
    • http://neogmbh.de/www/sites/default/files/userfiles/file/lunokawiwinusuxefatijovov.pdfIn PDF document text
    • http://danies.ru/ckfinder/userfiles/files/feliwevijarutez.pdfIn PDF document text
    • https://kitapkaplama.com/upload/ckfinder/files/xosasemevexomajowe.pdfIn PDF document text
    • http://le-lemniscus-incandescent.fr/ckeditor/upload/files/57028402797.pdfIn PDF document text
    • http://tearose-kitchen.com/sites/default/files/images/imcefile/xusebufuwopurakorijudol.pdfIn PDF document text
    • http://gadkowski.pl/repository/filemanager/file/14064653299.pdfIn PDF document text
    • http://adria-ex.com/images/blog/file/dubolimim.pdfIn PDF document text
    • https://schreinerheusi.de/wp-content/plugins/formcraft/file-upload/server/content/files/1614ff56e2b41e---41707267518.pdfIn PDF document text
    • https://bbu.vn/Images_upload/files/75719396698.pdfIn PDF document text
    • http://www.fotografoeventimilano.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139e35c5929f---4040872384.pdfIn PDF document text
    • http://abwrosedale.com/uploads/files/46304530901.pdfIn PDF document text
    • https://semut73.com/contents/files/zedogenoxozexone.pdfIn PDF document text
    • https://ozmutludokum.com/userfiles/file/90557569338.pdfIn PDF document text
    • http://theflowermaker.com/uploads/File/sinagudejezituwipij.pdfIn PDF document text
    • http://landpas.pl/upload/file/wovaruniwexibapusire.pdfIn PDF document text
    • http://ilturismoinitalia.it/userfiles/files/tovevigubux.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_off0001d35a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1D35A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001eb71.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1EB71 10532 bytes
SHA-256: 95fdace815edf2fdf315f33e5bb82528abb36aabaabc7f9e2e12eb58e9825cbc
font_02_sfnt_off00020361.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x20361 21184 bytes
SHA-256: 9a7ca3ac99229189818ef89c44fcd131a6f31c33e7b09adee27d70fff678283d