Malicious PDF — malware analysis report

Static analysis result for SHA-256 8c90c075eee1db0a…

MALICIOUS

PDF

77.9 KB Created: 2021-03-30 06:48:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f57394afe6f91b58c564f15e99f3ed6a SHA-1: ec6a26318d6cc58d0172197efdabb545a823ae98 SHA-256: 8c90c075eee1db0abd035c192cf169b9eedde8bc8de54f6c15fecb87739c7466
126 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs, many of which point to disposable hosting and are flagged as link farms. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware delivery. While no scripts were explicitly extracted, the PDF structure and embedded URIs suggest an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://ponafet.ru/wix?keyword=acnl+club+lol+opening+times
    • http://tinesemexogo.mygamesonline.org/23927577241.pdf
    • https://cdn.sqhk.co/tujujelo/4agcHp7/logegup.pdf
    • http://car-den.ru/gran_diccionario_oxford_espaol_ingles_descargar_gratisg5zcu.pdf
    • https://cdn-cms.f-static.net/uploads/4370063/normal_6018394ca0351.pdf
    • https://cdn-cms.f-static.net/uploads/4500199/normal_60506876dacb4.pdf
    • http://wrestling-mma.com/do_thorn_birds_really_existwupk2.pdf
    • http://mazipuvaxa.mywebcommunity.org/antecedentes_historicos_de_los_derechos_humanos_en_mexico.pdf
    • https://static.s123-cdn-static.com/uploads/4410727/normal_6006e867cf8c4.pdf
    • https://cdn.sqhk.co/budajawisore/gNvdibd/67663671716.pdf
    • http://bigowet.xyz/pencil_sketches_books_free_download5r9zw.pdf
    • https://cdn.sqhk.co/kixagixupo/igfbko7/dukiju.pdf
    • http://onlajn-kassa.ru/fun_math_worksheets_for_middle_school7rg4q.pdf
    • https://cdn.sqhk.co/lepavenujal/IidwlAi/58192920898.pdf
    • https://cdn-cms.f-static.net/uploads/4482206/normal_6054c93797c6c.pdf
    • http://slamelina.website/grays_anatomy_reviewgp2w8.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://nevabaza.atwebpages.com/what_is_thermal_processing_mean.pdf
    • https://e691ad07-92dc-45fa-af10-8929b4045ede.filesusr.com/ugd/87b9a8_63bbb8b77e584dc68550bca3a04ab7f8.pdf?index=true
    • https://uploads.strikinglycdn.com/files/f8515e3e-511e-43cc-b048-142afb85cf51/jexojulomejeg.pdf
    • https://f579be4a-c2ec-451d-94ee-532237c06880.filesusr.com/ugd/9f6a24_3ee80f2dc8d940b6bd142a700a42f090.pdf?index=true
    • https://uploads.strikinglycdn.com/files/1de9f82d-a5a0-4d31-a023-0f102ba85f05/38916006063.pdf
    • https://e33362eb-94ba-4427-a888-6f4863169a18.filesusr.com/ugd/36ce96_9fc72e3c443c45178f24e5a3a02efb02.pdf?index=true
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e325.bin
10336f5ad171c995d7cdf6ed249d99c4a113c392fb52d65c4f820463170594dc
pdf-font-stream PDF embedded font (sfnt) at offset 0xE325 4612 bytes
font_01_sfnt_off0000f378.bin
7128284b8057070b1d61b30cf16bf51bd87b4eeb55886180eafc16dfee501de3
pdf-font-stream PDF embedded font (sfnt) at offset 0xF378 5076 bytes
font_02_sfnt_off000104b2.bin
5fa058a1f752ec743bbf2444b13ff8fe0e1cba0aaf17308d3637cca36a847f04
pdf-font-stream PDF embedded font (sfnt) at offset 0x104B2 11228 bytes