Malicious PDF — malware analysis report

Static analysis result for SHA-256 aba3be97c20ebd25…

MALICIOUS

PDF

82.9 KB Created: 2021-09-20 02:22:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: b97d8691827a3d14548d858defcce1de SHA-1: 5e78d3ce8c73237ed62147f583da76199ddc4e11 SHA-256: aba3be97c20ebd2541286e8e244837a6c0112661f0197c96b7975ad023df66a3
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs pointing to other PDF files hosted on various domains, suggesting a link farm or content distribution network. The presence of PDF-specific heuristics like PDF_SEO_DISPOSABLE_LINK_FARM further supports the analysis of a link farm. While no scripts were explicitly extracted, the nature of PDF exploitation often involves embedded JavaScript for malicious actions.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

Heuristics 5

  • 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 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://bitree.net/ckfinder/userfiles/files/wajowajodemi.pdf In PDF document text
    • http://flygarfield.net/userfiles/file/lefumej.pdfIn PDF document text
    • http://ambulatorioveterinariomariani.it/userfiles/files/fedolefazujirixibipikal.pdfIn PDF document text
    • https://pirkitpadangas.lt/ckfinder/userfiles/files/17047772171.pdfIn PDF document text
    • http://xn--z92bzy85x.com/userData/board/file/mekule.pdfIn PDF document text
    • http://axwelindia.com/uploads/lomalubetajabineren.pdfIn PDF document text
    • http://rbtyutj01.com/userfiles/files/49619233176.pdfIn PDF document text
    • http://viettincapital.vn/upload/files/68433323306.pdfIn PDF document text
    • http://topas.lt/userfiles/file/83725320550.pdfIn PDF document text
    • http://artpolyclinic.com/file/files/58882290281.pdfIn PDF document text
    • http://alconsprom.ru/ckfinder/userfiles/files/95067734912.pdfIn PDF document text
    • http://indianspringhomes.com/userfiles/files/92020330914.pdfIn PDF document text
    • https://xn--90aweabvm.xn--p1ai/ckfinder/userfiles/files/45799456219.pdfIn PDF document text
    • https://workinhotel.com/upload/fckfile/kevexulodavevor.pdfIn PDF document text
    • https://oasis-travel.ro/files/wevonigaz.pdfIn PDF document text
    • http://hutbephottaihaiphong24h.com/upload/files/torejenuzuxanuxafijinob.pdfIn PDF document text
    • http://pension-erlkoenig.de/img/editor/file/fobaladuna.pdfIn PDF document text
    • http://training-solutions.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16147c5599d5c9---gudemapowe.pdfIn PDF document text
    • http://donghotam.com/luutru/files/dokasixivevutotamijifo.pdfIn PDF document text
    • https://kstraders.com/userfiles/file/wuxumeloxegijakonunozamu.pdfIn PDF document text
    • http://www.myhhsi.com/wp-content/plugins/super-forms/uploads/php/files/4dfdbaed8beafd783283d672b4a0f5aa/zafidapuvubar.pdfIn PDF document text
    • https://liur-krd.ru/userfiles/file/62266271773.pdfIn PDF document text
    • https://ons-station.com/editor_upload/file/posuvafokevuzewafomo.pdfIn PDF document text
    • http://szilasfood.hu/pic_upload/files/3279642050.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=how+to+hide+navigation+bar+on+androidPDF 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_off0000db5a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB5A 19588 bytes
SHA-256: 0055ec3ed2b10b8f3edefd477d74ee8a01002bac09f217ffb5e3b1c680905562
font_01_sfnt_off00010e16.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E16 10596 bytes
SHA-256: e6adb2c78f7d418f3526acd34f6d7b6a8980de7a1b3d96b865b0bc231e4fc9e6
font_02_sfnt_off00012609.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12609 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1