Malicious PDF — malware analysis report

Static analysis result for SHA-256 9afd88eb7418f535…

MALICIOUS

PDF

70.4 KB Created: 2021-06-10 16:47:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: 51c5a9c70e0052303ae64851cb93a480 SHA-1: 3c39db18d8d6c72074d91e52546e892183175005 SHA-256: 9afd88eb7418f53579df6203e4965f0bae718d960c763c544995606a0be63cbf
186 Risk Score

Malware Insights

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

This PDF file was identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains a large number of external links, many pointing to disposable hosting services, suggesting a link farm or phishing operation. The embedded content, though largely unreadable, includes references to 'Pubg kr best sensitivity' and the authoring application 'wkhtmltopdf', which may be part of a lure to direct users to malicious sites.

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
  • 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://crysiq.ru/pbw?utm_term=pubg+kr+best+sensitivity PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4370294/normal_600138cd75a4d.pdfIn PDF document text
    • https://zigetavut.weebly.com/uploads/1/3/0/8/130814179/7922168.pdfIn PDF document text
    • https://towizitubozabo.weebly.com/uploads/1/3/5/4/135400713/4583110.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4379355/normal_600d32e208cc3.pdfIn PDF document text
    • https://goguribepolim.weebly.com/uploads/1/3/0/7/130739596/2321128.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4404122/normal_6027d0a7dd958.pdfIn PDF document text
    • https://vakajufatig.weebly.com/uploads/1/3/5/3/135332685/wegurek.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4417523/normal_5fe7077ff1a55.pdfIn PDF document text
    • https://rajopolaxobi.weebly.com/uploads/1/3/1/4/131406270/dalupelarini-sedobidafov-janetako.pdfIn PDF document text
    • https://bifuwesulowun.weebly.com/uploads/1/3/4/3/134308915/jolifeb_datapojopino_pujanov_gamuvokijis.pdfIn PDF document text
    • https://tedaliduvif.weebly.com/uploads/1/3/5/9/135957254/75479f6.pdfIn PDF document text
    • https://vadurijale.weebly.com/uploads/1/3/4/5/134590900/5412943.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4450632/normal_601be0ef9b757.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4418575/normal_602809d6e1aaf.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4375077/normal_6015e8482fb1d.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4490133/normal_602ad5bdcc1f6.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/190cf0f8-2f07-4532-8852-abb8aacae922/rpg_maker_mv_character_generator_free_resources.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9d436ace-8d9a-4505-bebf-2f9bd835b466/5362278549.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/aa720552-757d-4c6a-8a67-4cc219252792/irobot_braava_jet_245_cleaning_solution.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4d96a3de-5889-4b9b-90ee-ea62ff616e4d/med_surg_1_hesi_practice_questions.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/68ecea3c-a2a7-4971-a9cf-6e40bc2f1eea/fuxofefebor.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/63ace438-d2c6-4405-9b6d-c55f43b03958/what_is_the_present_tense_of_listen.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6580c4ac-ad18-4cc7-8b3d-e45c96b3f301/52479022544.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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d851.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD851 4976 bytes
SHA-256: c41e5db8c4af4f0fbc23a6bc0c956ec394814c2e30f19e4a4d442cb81ab67158
font_01_sfnt_off0000e967.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE967 9820 bytes
SHA-256: 40b6d78ffe82ae2c663657ea26e117838c178f307e9f48a239d75ffc7f51f8db