Malicious PDF — malware analysis report

Static analysis result for SHA-256 816a331f1d3992db…

MALICIOUS

PDF

96.9 KB Created: 2021-07-20 10:16:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 0acf06cab028ca51e360d1ead49dd573 SHA-1: 2dad7655d723fbd8e756960a6e7d809627ff9df3 SHA-256: 816a331f1d3992dbe570ef742a6fa50bcd8aab62aa7751f70a6edd17d8b14eb0
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains a large number of links, many pointing to compromised or disposable domains, which is characteristic of a link farm used to distribute malicious content or phish for credentials. The presence of multiple PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM and PDF_SEO_DISPOSABLE_LINK_FARM heuristics further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9936

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://xn----gtbercbfedtm3b.xn--p1ai/admin/ckfinder/userfiles/files/9750328880.pdf In PDF document text
    • https://pametnidom.hr/pametne_kuce/userfiles/file/65523105955.pdfIn PDF document text
    • https://fietenhaardenenkachels.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160889afdc3e3b---lonorekopujo.pdfIn PDF document text
    • https://growmytruck.com/wp-content/plugins/super-forms/uploads/php/files/7efbb7d909b9b67c8d04e99e3fd81941/liribuxof.pdfIn PDF document text
    • http://auto-spec.ca/fck/file/sojeruvonidoget.pdfIn PDF document text
    • http://gramercygrand.ru/files/file/30477082586.pdfIn PDF document text
    • https://pinpointfeedtech.com/ckfinder/userfiles/files/49745779701.pdfIn PDF document text
    • http://goref.ru/files/file/tametexepovulodemoruna.pdfIn PDF document text
    • http://dbhsreunion.com/clients/21010/File/terowirerixebamo.pdfIn PDF document text
    • http://itnetworkconsultingsf.com/helpdesk/app/webroot/img/userfiles/files/36514330628.pdfIn PDF document text
    • http://themultifold.com/wp-content/plugins/super-forms/uploads/php/files/lq2g6c2kr92toekl5pfbnrpt91/46095206293.pdfIn PDF document text
    • https://www.goldenplanet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160c59e9742521---8798393924.pdfIn PDF document text
    • https://dubigroup.com/admin/fckeditor/editor/filemanager/connectors/upload/file/xarofomewadiduzajuladosu.pdfIn PDF document text
    • http://tamker.hu/userfiles/file/52776264209.pdfIn PDF document text
    • http://alarcon-v.com/editor_upload_image/file/64878793299.pdfIn PDF document text
    • http://videoacceso.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d2902690d10---dumelizutavanu.pdfIn PDF document text
    • http://arohitourandtravels.com/userfiles/file/12950509795.pdfIn PDF document text
    • https://resulgame.com/calisma2/files/uploads/nabovike.pdfIn PDF document text
    • https://kicksomeglass.com/wp-content/plugins/super-forms/uploads/php/files/0d8cf0436fa64d614f0081cec241dab4/bofitekekurimoseranubema.pdfIn PDF document text
    • https://ajwatravel.com/wheelmarine/userfiles/file/waxosabivuma.pdfIn PDF document text
    • https://travelstore.tn/userfiles/file/40122153407.pdfIn PDF document text
    • https://thepetrichortouch.com/wp-content/plugins/super-forms/uploads/php/files/jjojrm0p5983creogb576go38i/bifarusakinevij.pdfIn PDF document text
    • http://taniaandjohn.com/clients/874109/File/paleveluxaxokexaka.pdfIn PDF document text
    • https://marblobath.com/app/webroot/img/files/90704080527.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=rules+for+stealing+starsPDF 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_off0001160d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1160D 10532 bytes
SHA-256: 4478d5ce2ed870f22324ab6ecb22531c88a3f3a358e2330b5083133a3d8be128
font_01_sfnt_off00012e34.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12E34 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00014646.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14646 17644 bytes
SHA-256: cbe2556be8145cb498abc4b9270962c291c68dcbf428652fc6683689a5630cb6