Malicious PDF — malware analysis report

Static analysis result for SHA-256 ecf653b413034aa6…

MALICIOUS

PDF

100.9 KB Created: 2021-10-08 21:43:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 0e4575c83451d3ca2f71e4cb2d478881 SHA-1: c5afd430087d247539ecb17ed15c290310248c61 SHA-256: ecf653b413034aa651b8fac16ccf938117c4c883167c3296cdf0e83bc042bbbd
146 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF contains numerous embedded URIs, including one that points directly to an IP address, indicating an attempt to redirect users to potentially malicious content. The 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic further suggests that the document is designed to host a large number of links on disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9929

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
  • Clickable URI points to raw IP address medium PDF_URI_IP_LITERAL
    PDF contains a clickable HTTP(S) action whose host is a literal IPv4 address. Legitimate documents normally link to named domains; raw-IP destinations are common in disposable phishing and malware-delivery infrastructure.
  • 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 http://apsara.ru/userfiles/file/tegibupezafalivugemovul.pdf In PDF document text
    • http://140.121.125.49/ckfinder/userfiles/files/20210910_190723.pdfPDF link annotation
    • https://gangwontaxi.com/FileData/ckfinder/files/20210901_D9C88ED75B57C0AA.pdfIn PDF document text
    • http://newcompanyindia.com/admin/userfiles/file/82204950413.pdfIn PDF document text
    • https://cet.sk/res/file/larisuz.pdfIn PDF document text
    • https://www.tahitotfalu.hu/ckfinder/userfiles/files/41681239989.pdfIn PDF document text
    • http://mjengo.org/FCKeditor/editor/filemanager/connectors/php/connector.php?Command=FileUpload&Type=File&CurrentFolder=%2Ffile/24575728386.pdfIn PDF document text
    • https://thehouseproduction.net/file/xibenuwuwilanab.pdfIn PDF document text
    • http://steelbo.com/uploads/admins/u0/files/20210902105013.pdfIn PDF document text
    • http://bakersfield.thepokeluau.com/uploads/files/jubuge.pdfIn PDF document text
    • https://aventura-agence.lu/userfiles/files/78357660528.pdfIn PDF document text
    • http://chuanghuilaw.com/filespath/files/20210915155444.pdfIn PDF document text
    • http://prograsifkalip.com/files/kanim.pdfIn PDF document text
    • http://ponozky.gultio.cz/webpagebuilder/ckfinder/userfiles/files/87100735855.pdfIn PDF document text
    • http://hotelrefah4ter.ir/basefile/hotelrefah4terir/files/fajige.pdfIn PDF document text
    • http://lavalnerina.it/userfiles/file/lesared.pdfIn PDF document text
    • http://montazerangroup.com/uploader/file/40419125628.pdfIn PDF document text
    • https://vyaspublicschool.com/ckfinder/userfiles/files/32627180305.pdfIn PDF document text
    • https://ywint.com/ckfinder/userfiles/files/1631869574.pdfIn PDF document text
    • http://nontaromclinic.com/ckfinder/userfiles/files/57014227376.pdfIn PDF document text
    • http://art-lan.ru/uploads/assets/file/sikaduboje.pdfIn PDF document text
    • https://angelsforwarriors.org/userfiles/files/nobawopirunixejow.pdfIn PDF document text
    • http://bjbtrh.com/files/pic/file/gotefabefopizuvovezubat.pdfIn PDF document text
    • http://vibrosystem.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1612f4c948ab4a---82650137356.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=ghost+rider+tv+show+release+datePDF link annotation
    • 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00011f51.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F51 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00013768.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13768 10432 bytes
SHA-256: 14b6ca8800d0153971d5207687526dce3db0642f66bdc2f18fdfd06d7f6f742d
font_02_sfnt_off00014f44.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14F44 21316 bytes
SHA-256: 224af76e0b45e425a07bffbb4823405e977e223ab0a07317fe0c5f98571bbc29