Malicious PDF — malware analysis report

Static analysis result for SHA-256 dd77ddbd6e5bdf43…

MALICIOUS

PDF

86.2 KB Created: 2021-09-22 14:02:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 01bb08b7e3567557c31c97078ab426b0 SHA-1: c45251ea85fbcf0b507920d6d1fa8910e48425df SHA-256: dd77ddbd6e5bdf4360ecd317dda7197d3e50307668418a95fcb9dedb75fcfd8c
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, indicating a high likelihood of malicious intent. It contains numerous embedded URLs pointing to various domains, many of which are identified as part of a link farm on disposable hosting. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' strongly suggests the document's purpose is to redirect users to potentially harmful sites, likely for phishing or malware distribution. No scripts were extracted, but the sheer volume and nature of the URLs point to a malicious redirection scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

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 https://pistant.ru/uplcv?utm_term=curriculum+implementation+definition PDF link annotation
    • http://aurora-c.jp/files/files/gitoja.pdfIn PDF document text
    • https://somos.co/dleyes/admin/fotos/file/26167348632.pdfIn PDF document text
    • http://top-caster.com/userfiles/file/lasesegexifikokolezed.pdfIn PDF document text
    • http://ghinelliarchitettura.it/userfiles/files/gigadatavawitojoko.pdfIn PDF document text
    • http://www.expertnutritionadvisor.com/wp-content/plugins/formcraft/file-upload/server/content/files/161466c9d0fa9a---68742736535.pdfIn PDF document text
    • https://www.casestilistas.es/ckfinder/userfiles/files/fegumekida.pdfIn PDF document text
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/qgq45eobqoqcmmtmk4h4okm0h6/zejiw.pdfIn PDF document text
    • https://full-e.com/app/webroot/userfiles/files/20210921_100338.pdfIn PDF document text
    • http://maxbrio.kr/files/files/59383597702.pdfIn PDF document text
    • http://makesomenoise.hu/upload/file/51027089118.pdfIn PDF document text
    • http://sentezetutmerkezi.com/upload/ckfinder/files/92102023227.pdfIn PDF document text
    • http://veterinariacasettamattei.it/userfiles/files/26714713255.pdfIn PDF document text
    • http://bugaboo-buffalo.eu/UserFiles/File/wowem.pdfIn PDF document text
    • https://premium-house.uz/images/file/2338731775.pdfIn PDF document text
    • https://propiedades.net/ckfinder/userfiles/files/4835214861.pdfIn PDF document text
    • http://hani-bee.com/userfiles/files/mamufexanozoz.pdfIn PDF document text
    • http://annabarons.lv/files/files/125606378.pdfIn PDF document text
    • http://placidlakes.com/larpm/uploads/file/89330655155.pdfIn PDF document text
    • https://granitabrasive.com/editor_up/46295088265.pdfIn PDF document text
    • http://serenetour.com/image/upload/File/denemifetipasusiguwi.pdfIn PDF document text
    • https://wic-net.com/userfiles/file/96656724359.pdfIn PDF document text
    • http://michael-dhom.com/webseiten/file/zobatogimopibij.pdfIn PDF document text
    • https://www.jaegeraviation.com/ckfinder/userfiles/files/debosoxeka.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_off0000edae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDAE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000105c0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105C0 17528 bytes
SHA-256: ab6b6acdae707012fb42590859c0ca2494398e035b4ee931cc909097fc4bc655
font_02_sfnt_off000132d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x132D5 10744 bytes
SHA-256: d9d0ea70e55ac2034d6f3e6ae5b722ffd00bf06d0169d3046300831001efe887