Malicious PDF — malware analysis report

Static analysis result for SHA-256 721ec2d2802e64e0…

MALICIOUS

PDF

69.5 KB Created: 2021-04-05 15:19:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-02
MD5: 4daae0e29805cb7bfac6ea84bcf5f28b SHA-1: fbb7bfdf4c1e067ced019ce7476ab5db0a1b7368 SHA-256: 721ec2d2802e64e0b0d4fba7339f8409049880cfeac01bb3000108b3a8cebd6b
186 Risk Score

Malware Insights

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

This PDF file was identified as malicious by a machine learning classifier and ClamAV, indicating a high likelihood of malicious intent. The file contains a large number of external links, suggesting it functions as a link farm, potentially for SEO manipulation or to distribute further malicious content. While no scripts were explicitly extracted, the PDF structure and numerous external URIs point towards techniques used in phishing or malicious redirection schemes.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 6

  • 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 contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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://kuzutuzo.ru/award?keyword=passive+verbs+exercises+pdf PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4446147/normal_600f3fcaa5ad7.pdfIn PDF document text
    • http://wugumonisukanib.sportsontheweb.net/14561134521.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4408195/normal_60413e47e7330.pdfIn PDF document text
    • https://sawuwirepugasup.weebly.com/uploads/1/3/0/9/130969548/nazibokidu-kewibejizi-lewapumifoxa.pdfIn PDF document text
    • http://finuxezanasa.mygamesonline.org/2396321585.pdfIn PDF document text
    • https://gasuzenop.weebly.com/uploads/1/3/4/2/134266144/3f76ceb.pdfIn PDF document text
    • https://zaxifugerabapaz.weebly.com/uploads/1/3/1/0/131071175/gozakanon.pdfIn PDF document text
    • https://lazesomixasima.weebly.com/uploads/1/3/4/5/134588612/puxusu.pdfIn PDF document text
    • http://lumobumekola.getenjoyment.net/chapter_1_encounters_and_foundations_to_1800_answers.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4382208/normal_601143bda9fa3.pdfIn PDF document text
    • https://cdn.sqhk.co/lofakekaf/hgPnpjh/red_sun_rising_the_violent.pdfIn PDF document text
    • https://cdn.sqhk.co/lamiwifa/jijdgen/12846842197.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://xovolefewawex.atwebpages.com/xuxor.pdfIn PDF document text
    • http://positajugopisu.myartsonline.com/pizukobojanakolewekipat.pdfIn PDF document text
    • https://0298dc5a-7924-4276-8279-06452a5288da.filesusr.com/ugd/b30cf0_62967839300a40878bcf55c4217264fe.pdf?index=trueIn PDF document text
    • http://buzumigasox.myartsonline.com/rewrite_sentences_exercises_advanced.pdfIn PDF document text
    • https://ec08fec6-e576-400d-8504-372613838d3c.filesusr.com/ugd/57e0ce_06707ee7bb1e4e2f85faef8fe3cb5f4e.pdf?index=trueIn PDF document text
    • https://6e7ef639-f89a-4701-86f9-710a836f1183.filesusr.com/ugd/12745a_add48b2944d44d399bb54c8b8c9cb629.pdf?index=trueIn PDF document text
    • http://fuvuvadut.onlinewebshop.net/malerasulaxumovugogomusak.pdfIn PDF document text
    • https://d451e762-8e00-4155-9971-9512d28d2528.filesusr.com/ugd/b52961_b3b3c284ecc44fc482dd7927d1cf50ab.pdf?index=trueIn 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_off0000d39e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD39E 5388 bytes
SHA-256: 1f88fc7e727635ea4ee4e2029a44f8f854cf1d532fa97625e91f34354f8441d8
font_01_sfnt_off0000e605.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE605 10148 bytes
SHA-256: 658a07e45af847a6a6ace9f082da2f030e117a49f059fbbb825b40097d877311