Malicious PDF — malware analysis report

Static analysis result for SHA-256 e4577ee4aea74a1d…

MALICIOUS

PDF

82.8 KB Created: 2021-05-13 06:10:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-20
MD5: 588e4858851f393ccd68141be00a7dd4 SHA-1: 7d53843c612344b08d8815af47af94a844b76548 SHA-256: e4577ee4aea74a1d6b8c7a24f40aa3ef406df46a59fcd2116f0b1c088404aa90
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution T1059.007 JavaScript

The PDF file contains a large number of external links, many pointing to disposable hosting services, indicative of a link farm or phishing operation. The ClamAV detection and ML classifier strongly suggest malicious intent, specifically identified as Pdf.Phishing.Trojan. The embedded URLs, such as 'https://nipisod.ru/strik?utm_term=read+and+speak+korean+for+beginners+book', are likely used to redirect users to malicious content or phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://nipisod.ru/strik?utm_term=read+and+speak+korean+for+beginners+book PDF link annotation
    • https://towodoruzaxigol.weebly.com/uploads/1/3/6/0/136050186/9607032.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4467581/normal_60061e0932be4.pdfIn PDF document text
    • http://damvglaz0.xyz/pali_canon_meaning_in_englishyqjez.pdfIn PDF document text
    • http://latencfsrt.space/whirlpool_bottom_freezer_refrigerator_not_cooling_or_freezing55k4h.pdfIn PDF document text
    • https://fijoxivivuf.weebly.com/uploads/1/3/4/0/134041864/7838e4d3b2.pdfIn PDF document text
    • http://baby-slings.ru/dipemuzabidanowilolokava9j946.pdfIn PDF document text
    • https://zezawimikosalef.weebly.com/uploads/1/3/5/3/135329884/tazun-xukupuwusolud.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4408348/normal_60655553d5c90.pdfIn PDF document text
    • https://vamotavobepud.weebly.com/uploads/1/3/1/4/131438348/5350241.pdfIn PDF document text
    • https://bigevavez.weebly.com/uploads/1/3/4/0/134016854/7476779.pdfIn PDF document text
    • http://003-center.ru/sab_gertrudis_gomez_de_avellaneda_analisisp4sxz.pdfIn PDF document text
    • https://zepukuliro.weebly.com/uploads/1/3/5/9/135964459/f854441d.pdfIn PDF document text
    • https://jazolesapixol.weebly.com/uploads/1/3/1/4/131453041/2088917.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://uploads.strikinglycdn.com/files/3c591ff8-ccc1-40b0-88da-e96dd3187e0e/criminal_defense_attorneys_in_houston_texas.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/65d9e857-d976-48a8-9a9b-92b6440fbc81/madutimurunarujibasexedi.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/58f26ee8-6732-4238-a9ff-6964637b2e7b/latest_john_grisham_books_in_order.pdfIn PDF document text
    • https://s3.amazonaws.com/dipafuxe/risivoput.pdfIn PDF document text
    • https://s3.amazonaws.com/jejulurowev/infinite_painter_user_guide.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f9b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9B0 5096 bytes
SHA-256: 31281a2b89ace17bafc6de8221a637237fdeee7eaf39f0c501ed2040df529c97
font_01_sfnt_off00010b0d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B0D 10936 bytes
SHA-256: 459da5220c71a5915c79247ff4546d12268844a3a1534df8dbb28a0a949d15dd
font_02_sfnt_off0001301d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1301D 4324 bytes
SHA-256: 1158d95dac44631f497756703988ba3645251422e7ff0015d3fca430225e7c3e