Malicious PDF — malware analysis report

Static analysis result for SHA-256 c5017cf110e7dd68…

MALICIOUS

PDF

80.4 KB Created: 2021-07-13 20:00:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-16
MD5: 1fbb923b0f504c6c9f91f811b6d7864b SHA-1: 7ec9b1402487eb6a086a8aced32f615679ffa09e SHA-256: c5017cf110e7dd68402f6ecf84d5c3a2e52795d7bb5bed0432569eb5ce76b084
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It functions as a link farm, directing users to multiple external URLs hosted on various domains, some of which appear to be compromised. The document body is heavily obfuscated, preventing a clear understanding of its specific lure, but the overall structure suggests an attempt to lead users to malicious content or exploit kits.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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://adacu.org/userfiles/file/20210629183215.pdf In PDF document text
    • http://vorne-sitzen.eu/pcms/content/file/68533661652.pdfIn PDF document text
    • http://anonelectronics.com/admin/fckeditor/editor/filemanager/connectors/php/upload_jpg/file/202106301904435609.pdfIn PDF document text
    • http://1utilaje.ro/mm/file/lopiked.pdfIn PDF document text
    • https://www.revistadefiesta.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a867bb4bc45---gefilelezowefezuf.pdfIn PDF document text
    • http://herodumpsterrental.com/wp-content/plugins/super-forms/uploads/php/files/f1676a4c18dea5d203e4e9425fee4911/18798641245.pdfIn PDF document text
    • https://agilitynd.com/wp-content/plugins/super-forms/uploads/php/files/6cf1025d8941ac9d26c55655b726b56e/79207198462.pdfIn PDF document text
    • http://bioscipublisher.com/files/upfiles/file/refejizabom.pdfIn PDF document text
    • https://htfcompact.com/wp-content/plugins/super-forms/uploads/php/files/d6311ce2a43d9cd915ec61818b6b6b3a/sorasaxititun.pdfIn PDF document text
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/1606cb466b4365---12271303653.pdfIn PDF document text
    • https://lawpropertyconsultants.co.uk/wp-content/plugins/super-forms/uploads/php/files/ing817p6hc2f3va30ger34u46i/2282449806.pdfIn PDF document text
    • https://auf.vn/wp-content/plugins/super-forms/uploads/php/files/4uu95hhrll3sl1c05prh8cs836/gelufusapakipafof.pdfIn PDF document text
    • https://amrapalispot.com/userfiles/file/26644035733.pdfIn PDF document text
    • http://yatros.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160aac5bdcb1ff---92210217078.pdfIn PDF document text
    • https://ferest.ro/imagini_ws/tizabapipejaxis.pdfIn PDF document text
    • http://queuemanagementsystems.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085685c61969---34571405003.pdfIn PDF document text
    • http://samuiluxurytravel.com/Uploads/file/82606441152.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=hydraulic+system+and+pneumatic+systemPDF 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_off0000da18.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA18 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f22f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF22F 10760 bytes
SHA-256: 4c00842821ac29fe088174d7a8e80602e16bd3ed4a2168750e43ba8b565dd172
font_02_sfnt_off00010adb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10ADB 16112 bytes
SHA-256: 8705acf35df552a311dc94027dd9801cbe9b98e31b5a3ea78798ff6c0404747f