Malicious PDF — malware analysis report

Static analysis result for SHA-256 644b076a1eb1de9a…

MALICIOUS

PDF

89.3 KB Created: 2021-06-13 16:56:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: d776c4ec90bcf2b135da48eebc970e85 SHA-1: cab91a5ff05c68e86295bb2394fc4b9afb9177d6 SHA-256: 644b076a1eb1de9afa30578a27084ac969619a3c8744e50baff1b4ebafc37780
186 Risk Score

Malware Insights

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

This PDF file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The file contains a large number of external links, many hosted on disposable domains, suggesting a link farm or SEO spam operation. The embedded URLs, such as 'https://infrive.ru/pbw?utm_term=best+clash+of+clan+base+town+hall+9', are likely used to redirect users to malicious or unwanted content. No scripts were extracted, but the PDF structure itself is designed to host and present these links.

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://infrive.ru/pbw?utm_term=best+clash+of+clan+base+town+hall+9 PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4485935/normal_602722a97e56d.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4531626/normal_5fd85e1805ac1.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4391024/normal_602c5abbe9e02.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4499299/normal_60689164f1c15.pdfIn PDF document text
    • https://sekepavikaforo.weebly.com/uploads/1/3/4/6/134608196/86604.pdfIn PDF document text
    • https://wopipobije.weebly.com/uploads/1/3/4/8/134889886/612ebf55d.pdfIn PDF document text
    • https://suxaposalepet.weebly.com/uploads/1/3/4/6/134677753/6346131.pdfIn PDF document text
    • https://vasejafarobi.weebly.com/uploads/1/3/1/4/131454155/kiwularebul-lemutikod-vapati.pdfIn PDF document text
    • https://tejitopojod.weebly.com/uploads/1/3/4/7/134737109/8199790.pdfIn PDF document text
    • https://mukojemugasab.weebly.com/uploads/1/3/5/3/135314074/tubipigudikuroso.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4386851/normal_5fe454846f24b.pdfIn PDF document text
    • https://mamonujiduvef.weebly.com/uploads/1/3/4/5/134525279/3544359.pdfIn PDF document text
    • https://xoraxabaxid.weebly.com/uploads/1/3/2/6/132682630/8c6ab.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://beratirupo.pbworks.com/f/hp_officejet_4500_wireless_setup_wizard.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a007f9ac-4aee-45a6-9e80-43c10327c4d3/garmin_drive_50lm_5_sat_nav_review.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5d1a1778-a50e-4147-93be-fc1cf7a7f50f/what_is_king_henry_died_by_drinking_chocolate_milk.pdfIn PDF document text
    • http://zanopadik.pbworks.com/w/file/fetch/145170906/valupewumazazeka.pdfIn PDF document text
    • http://wemekojezum.pbworks.com/w/file/fetch/144670779/oracle_interview_questions_for_java_developer_2_years_experience.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/eda862d5-47c4-431d-9022-8d4f263016de/93993365680.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6db249a4-2349-4154-8bfc-4b0d772e90ab/rousseau_social_contract.pdfIn PDF document text
    • http://doxawadar.pbworks.com/w/file/fetch/144495294/4267942199.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_off000112d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x112D5 3080 bytes
SHA-256: 1cbe04544191bb30a7a97009dc1511722b9e066f78f54459ada3b33b96b99d4f
font_01_sfnt_off00011dd2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DD2 5308 bytes
SHA-256: 40cf99ca5f06cbc6c4cfcb3fb4f236ceb22c9d8654a274dfeec2647765b99da0
font_02_sfnt_off00012ffd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12FFD 11480 bytes
SHA-256: 84e4bc143cbd299de2a2672b911955fd8f75d1be4219bb2f10f4036e5430845a