Malicious PDF — malware analysis report

Static analysis result for SHA-256 8e5523dd48b88dbf…

MALICIOUS

PDF

82.9 KB Created: 2021-09-11 06:58:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-22
MD5: dba198bd75b3b1425045e4cf1d32947d SHA-1: 9cd4984805662032aa3d8a1379d1b97c2c03efee SHA-256: 8e5523dd48b88dbfa135ec32a0e4eb67a63f69fc4feaea099cbac2b76c250e4d
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as a malicious PDF by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous embedded URLs pointing to various domains, suggesting a phishing or link farm operation. The heuristic PDF_SEO_DISPOSABLE_LINK_FARM further supports this, indicating the PDF is designed to redirect users to multiple disposable hosting sites, likely for credential harvesting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 5

  • 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 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/uplcv?utm_term=home+office+login+365 PDF link annotation
    • https://vyaspublicschool.com/ckfinder/userfiles/files/83535334862.pdfIn PDF document text
    • http://crmrealty360degree.in/userfiles/file/figikavad.pdfIn PDF document text
    • http://ferien-in-zahren.de/images/file/sasega.pdfIn PDF document text
    • http://pusancard.com/userData/board/file/65083701597.pdfIn PDF document text
    • http://hertzlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/xodikapixisup.pdfIn PDF document text
    • http://rezidencianestor.sk/app/webroot/files/ckeditor/files/37119739760.pdfIn PDF document text
    • https://backcountryplayground.com/wp-content/plugins/super-forms/uploads/php/files/dce4ce6a003eebd3937d8694d65eaae5/31207625429.pdfIn PDF document text
    • http://freetds.net/userfiles/file/60174092699.pdfIn PDF document text
    • http://campingwithconvenience.com/files/files/wefiduwoberur.pdfIn PDF document text
    • http://akcjonariusz.com/UserFiles/file/moponugapaze.pdfIn PDF document text
    • https://sdhouse.info/ckfinder/userfiles/files/filidon.pdfIn PDF document text
    • http://travel-door.com/userfiles/file/56278931759.pdfIn PDF document text
    • https://watertorens.nl/userfiles/file/82708260423.pdfIn PDF document text
    • http://santamariamikado.com/uploads/files/308919297.pdfIn PDF document text
    • http://uteambio.com/upload/files/vumusikawise.pdfIn PDF document text
    • https://liantoong.com/archive/upload/files/sepobefubobelunuratako.pdfIn PDF document text
    • https://magazinul-de-instalatii-sanitare.ro/app/webroot/files/userfiles/files/xojowime.pdfIn PDF document text
    • http://open.ua/uploads/ckeditor/files/80097712711.pdfIn PDF document text
    • http://sqc.jp/user_data/editor/ckfinder/core/connector/php/upload/files/nujok.pdfIn PDF document text
    • http://husplaza.hu/editor_up/21669137652.pdfIn PDF document text
    • http://polimak.pl/userfiles/file/1799085056.pdfIn PDF document text
    • http://kozelsk-adm.ru/files/uploads/files/66986788574.pdfIn PDF document text
    • http://ministryofrum.com/memlogos/file/86998210285.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://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_off0000dea7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDEA7 10616 bytes
SHA-256: 0a4ef5c874afe428b6b7a4bc12c19171ad0e1666536e3d1d29f4dfe7d9e6f08d
font_01_sfnt_off0000f6d9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6D9 18216 bytes
SHA-256: 6b567570cdc3a9209c6e066884bce55f69f487bb5422f3824407c6791713b6e1
font_02_sfnt_off000125d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x125D1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1