Malicious PDF — malware analysis report

Static analysis result for SHA-256 947f7e00b9b8a0f5…

MALICIOUS

PDF

81.5 KB Created: 2021-03-18 09:11:51 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-21
MD5: b031bcc3b2c7d1f7e2819dca28c40917 SHA-1: f3e832ff4fa8f433fce4be787f2f211f01b7f463 SHA-256: 947f7e00b9b8a0f5a6c9253b9b77a3e6a2e77939921421cb06f136113f4df211
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file contains a large number of external links, many pointing to other PDF files, indicating a link farm for SEO manipulation or content distribution. ClamAV detected this as Pdf.Phishing.Trojan, and ML classification strongly suggests maliciousness. The embedded URL `https://jacksth.ru/strik?utm_term=que+clases+de+titulos+de+credito+existen` is likely part of the malicious infrastructure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://jacksth.ru/strik?utm_term=que+clases+de+titulos+de+credito+existen PDF link annotation
    • https://cdn.sqhk.co/silakozafi/agi5zji/avengers_xbox_one_x_gameplay.pdfIn PDF document text
    • https://cdn.sqhk.co/ferudati/jiijicE/amrapali_full_movie.pdfIn PDF document text
    • https://cdn.sqhk.co/tefaxobaf/cgdIrjt/crowder_my_sweet_lord_lyrics.pdfIn PDF document text
    • https://cdn.sqhk.co/jawuraxexije/mDkjhDt/51168626674.pdfIn PDF document text
    • http://dawavuwera.22web.org/jepeterakirujiremus.pdfIn PDF document text
    • https://cdn.sqhk.co/kixikeli/iiobMx5/55108712645.pdfIn PDF document text
    • https://cdn.sqhk.co/kobewudojuvo/gSasAgh/united_airlines_plus_points_upgrade.pdfIn PDF document text
    • https://cdn.sqhk.co/kurafuso/Odhj5jd/fosakovipejip.pdfIn PDF document text
    • https://cdn.sqhk.co/xumelesep/U3gjhaR/gupifa.pdfIn PDF document text
    • http://pozonewexoz.iblogger.org/77131545370.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://1ec9b6e7-17eb-4e1e-a994-ba5ce4cbdb7c.filesusr.com/ugd/d4a9d6_57d21e55baae42f2821ec4310f5893ad.pdf?index=trueIn PDF document text
    • https://b56e00ce-d729-42e9-814b-b9a4b194f5ba.filesusr.com/ugd/f6f93f_73f2ec7947b0422aaa8fd9cc852c3620.pdf?index=trueIn PDF document text
    • http://jalijoruki.atwebpages.com/chemistry_book_2nd_year.pdfIn PDF document text
    • https://4541bc1c-e35c-4de3-bb44-1f53c3e1a56d.filesusr.com/ugd/68f66e_08c49c3847b1420b8f4a57449f706211.pdf?index=trueIn PDF document text
    • https://8a5a474a-a671-4857-921d-d1df0ee72544.filesusr.com/ugd/523716_b079df2fe1aa4678a54ffe9e43ab7810.pdf?index=trueIn PDF document text
    • https://8b7199fc-a029-4910-8138-caee300d1cbd.filesusr.com/ugd/da8f68_28ee1df4939b4d03a358c3f632d105dc.pdf?index=trueIn PDF document text
    • http://safodur.epizy.com/vixitaxeniwugesabakaxo.pdfIn PDF document text
    • https://5f90d536-2a72-4461-adff-280afd3056cb.filesusr.com/ugd/27c394_79d529d4f6db4ad8a7237c5a7ece23b6.pdf?index=trueIn PDF document text
    • http://kibotiriponikew.rf.gd/manual_de_microbiologia_veterinaria.pdfIn PDF document text
    • https://5563968e-3cf5-463b-8312-7915ab8a4794.filesusr.com/ugd/cd90d1_345b8fd65f844a63802d872ca8093ae9.pdf?index=trueIn PDF document text
    • https://d497f082-4895-42de-a72c-038d9367c8a3.filesusr.com/ugd/8e727b_ba81f94f5b6e42258654047f39789155.pdf?index=trueIn PDF document text
    • https://101c3d73-5e22-4da1-a203-a3a2a794ce88.filesusr.com/ugd/69a512_50e616d263254a8093116a8877c1ca30.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_off00010002.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10002 5060 bytes
SHA-256: 28cdecae2c9cf9cd505bdc888c5114d76e0de65e68c32b9f2295f38375b0eca6
font_01_sfnt_off00011147.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11147 11564 bytes
SHA-256: 948b6208c3b41b92492d4c7275a4573ce5fea289aac0769e8e87d625b200c092