Malicious PDF — malware analysis report

Static analysis result for SHA-256 ff55b3b92f9154b6…

MALICIOUS

PDF

89.3 KB Created: 2021-04-01 21:08:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-14
MD5: ea60a4cdc690dafc833d31711f25206c SHA-1: d4f975a6bd6e03249a70d3cfc5ee624fbfd54d08 SHA-256: ff55b3b92f9154b6aa71e934c34c3efb842355b5a95f3dae27825cfa3aadec12
186 Risk Score

Malware Insights

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

The PDF contains a significant number of external links, with many hosted on disposable domains, indicating a link farm designed to distribute potentially malicious content or engage in SEO spam. ClamAV detection and ML classification strongly suggest malicious intent, likely related to phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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://xajibur.ru/123?utm_term=multitasking+debate+ielts+reading+answers PDF link annotation
    • http://rijepesejib.22web.org/nusonira.pdfIn PDF document text
    • http://pifafixejizigu.scienceontheweb.net/lujos.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://7f58a6d3-5723-489e-a2bd-17fd91e1ddd5.filesusr.com/ugd/655495_9fc1cebde46f42dda77209a36212218d.pdf?index=trueIn PDF document text
    • https://63b1f34b-4847-450f-8d9a-4788d10e1cf5.filesusr.com/ugd/451a43_84f9b4af472c49a0b5abc4487a23315b.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/63c9b584-e436-4734-bd97-285e18a4d171/computer_programming_books_download.pdfIn PDF document text
    • http://kemiwadosu.rf.gd/microsoft_access_vba_macro_programming.pdfIn PDF document text
    • http://tuvatopuvonu.epizy.com/free_beginning_cursive_writing_worksheets.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/20fe7fd2-554a-4108-ad73-672e0870eabd/kupabunebizomaxejozejaxor.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ffc9feee-2804-44ee-8be6-6b41cb6be068/617405917.pdfIn PDF document text
    • https://s3.amazonaws.com/xesigeze/what_genre_is_robinson_crusoe.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/18677757-2bb2-4ab4-bebc-0997ae44d8a0/bizenifuvo.pdfIn PDF document text
    • http://tikimiwuwal.myartsonline.com/mogonoxed.pdfIn PDF document text
    • http://sanikivatuma.rf.gd/24014448617.pdfIn PDF document text
    • https://s3.amazonaws.com/midizaxopazeji/advanced_java_concepts_with_examples.pdfIn PDF document text
    • http://bapexuzajo.epizy.com/aruba_ap_115_datasheet.pdfIn PDF document text
    • http://xisefaduruke.rf.gd/50602817081.pdfIn PDF document text
    • https://s3.amazonaws.com/gewuwasi/analyseries_2._0_manual.pdfIn PDF document text
    • https://s3.amazonaws.com/mokuwanibof/lelalaregotejajajupano.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/fb53f9dd-7dc6-4155-8ddd-b04eb57011ae/math_logic_puzzle_solver.pdfIn PDF document text
    • http://guzeberipavol.rf.gd/tevamutex.pdfIn PDF document text
    • http://jogufek.epizy.com/gijapex.pdfIn PDF document text
    • https://434dcbc4-7bd9-40fe-99bf-e102daebf961.filesusr.com/ugd/07ef24_cb4da62e15e546bf83a0382aaf57faf7.pdf?index=trueIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00011fcc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11FCC 5292 bytes
SHA-256: 5b9754634fb471f2b48621d7527366fb880f8b7fc8c0e3a5afc2ea7b4703f441
font_01_sfnt_off000131f3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x131F3 10676 bytes
SHA-256: eb08150107393b3c9e66a2ced6f8b0e3a812a080e482cbfbe45a97556e551b49