Malicious PDF — malware analysis report

Static analysis result for SHA-256 d5ab455ce3e051e3…

MALICIOUS

PDF

76.1 KB Created: 2021-06-10 10:09:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: 4ee5b777113bede7f2e3d82f8741ea49 SHA-1: 6949e60092b6ee1baea3c641d692b2ad2e31bbf2 SHA-256: d5ab455ce3e051e31ad64b69b82331dfecf816ef9b5d1cb27d03ed65f973d7b6
126 Risk Score

Malware Insights

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

The sample is a PDF document identified as malicious by ML classifiers and ClamAV. It contains numerous embedded URLs, with a primary suspicious URL pointing to 'crysiq.ru'. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a large number of links to disposable hosting, suggesting a link farm used for SEO manipulation or to host malicious content. No scripts were extracted, but the presence of external links and the overall detection suggest a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://crysiq.ru/pbw?utm_term=directions+esl+worksheet PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4485162/normal_602d6a698484b.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • http://nilanom.pbworks.com/f/how_to_cancel_brinks_security.pdfIn PDF document text
    • http://morabef.pbworks.com/w/file/fetch/144673041/campo_magnetico_ejercicios_resueltos_universidad.pdfIn PDF document text
    • http://mukonisu.pbworks.com/w/file/fetch/144447159/how_to_create_an_interactive_in_indesign_cs6.pdfIn PDF document text
    • http://luwapoveduvi.pbworks.com/f/92909961599.pdfIn PDF document text
    • http://jevibufile.pbworks.com/w/file/fetch/144626856/fimukivuwijuginasenolo.pdfIn PDF document text
    • http://zizovitunex.pbworks.com/w/file/fetch/144483039/38511919226.pdfIn PDF document text
    • http://mumasenekera.pbworks.com/w/file/fetch/144424017/what_to_expect_when_youre_expecting_book_kmart.pdfIn PDF document text
    • http://sizolasipape.pbworks.com/w/file/fetch/144870132/lebemulajobumiruku.pdfIn PDF document text
    • http://kibumezi.pbworks.com/w/file/fetch/144455838/kusimemozamapasem.pdfIn PDF document text
    • http://gogoporiwo.pbworks.com/f/romeo_and_juliet_1996_full_movie_download_hindi_dubbed.pdfIn PDF document text
    • http://vawijoj.pbworks.com/w/file/fetch/144661506/rejogifosewikojipa.pdfIn PDF document text
    • http://zigunef.pbworks.com/w/file/fetch/144455784/how_to_price_items_in_moonlighter.pdfIn PDF document text
    • http://xesimisejek.pbworks.com/f/36233731177.pdfIn PDF document text
    • http://misabovu.pbworks.com/w/file/fetch/145026447/17113839858.pdfIn PDF document text
    • http://laxaxufudej.pbworks.com/w/file/fetch/144491499/73382294005.pdfIn PDF document text
    • http://jedilukiwo.pbworks.com/w/file/fetch/144656421/the_mabinogion_best_translation.pdfIn PDF document text
    • http://figuduvimeti.pbworks.com/f/animal_adaptations_worksheets_4th_grade.pdfIn PDF document text
    • http://moxulolo.pbworks.com/f/google_forms_not_working_today.pdfIn PDF document text
    • http://giribuv.pbworks.com/f/rijojok.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_off0000e081.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE081 4620 bytes
SHA-256: 90907789f985609552766477d908333c63edac3f60a4f5f7f6219d8598fa8a83
font_01_sfnt_off0000f030.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF030 10864 bytes
SHA-256: a20de27567d31f0a269514954b50e6a5abf1250e43982d9c809e82153899816b
font_02_sfnt_off000114af.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x114AF 4324 bytes
SHA-256: cd94ef65598b1866d0653cdd88243d989fd81359c0e770c2d3a4858f1c2f6d34