Malicious PDF — malware analysis report

Static analysis result for SHA-256 824490439f537212…

MALICIOUS

PDF

76.8 KB Created: 2021-02-28 10:32:15 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-18
MD5: 0bb0ae8d9e353fcc76927bc2b8558660 SHA-1: 4680fdc19dc0f4e53c8aa70efd92a6407a8c50d9 SHA-256: 824490439f537212bc0cf6816c023b4f537d2c6de46f1eab29c0f3432f73ab9e
134 Risk Score

Malware Insights

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

The sample is identified as malicious by ML classifiers and ClamAV, and exhibits characteristics of a link farm hosted on disposable domains. The document body, though heavily obfuscated, suggests a lure related to 'infinitive gerund participle exercises with answers pdf'. The presence of numerous external URIs, many pointing to disposable hosting, indicates an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://bologen.ru/123?utm_term=infinitive+gerund+participle+exercises+with+answers+pdf PDF link annotation
    • https://nalelijuw.weebly.com/uploads/1/3/4/5/134512153/gebesawuranefup.pdfIn PDF document text
    • http://becloud.website/persyaratan_sim_c_20190x39m.pdfIn PDF document text
    • http://gexopidikimo.mygamesonline.org/how_to_login_into_your_icloud_account.pdfIn PDF document text
    • https://pidowiwosuzaji.weebly.com/uploads/1/3/0/9/130969191/dizulafevorapa.pdfIn PDF document text
    • http://zutatowatipo.mywebcommunity.org/47162563194.pdfIn PDF document text
    • http://naderuromopuru.22web.org/wepanukigavatolasivi.pdfIn PDF document text
    • http://xojudesabesone.66ghz.com/bootstrap_modal_input_form_example.pdfIn PDF document text
    • http://barajofa.mywebcommunity.org/25473741142.pdfIn PDF document text
    • http://jilet1.club/worksheet_works_diamond_math_problemsvc6v0.pdfIn PDF document text
    • http://zawugudumi.getenjoyment.net/what_is_the_best_process_improvement_methodology.pdfIn PDF document text
    • http://femuxeririta.mygamesonline.org/what_is_an_extraneous_solution_example.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://zisafaziga.epizy.com/bsf_online_form_10th_pass_2018.pdfIn PDF document text
    • http://javasuk.epizy.com/gexejejuze.pdfIn PDF document text
    • http://ridabus.epizy.com/jexodisela.pdfIn PDF document text
    • http://wiferowifi.rf.gd/100_verbos_regulares_en_ingles_en_presente_pasado_y_participio.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000eef0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEF0 5572 bytes
SHA-256: 8e76131c670333ec692e1a9446d112ea75142ce883453061e15cf23caea0fc1f
font_01_sfnt_off000101ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x101FF 10460 bytes
SHA-256: 98db4a9aab06b77d3f0fdaa9ecdb037781210c99f03df085f5b9f1977685d6cf