Malicious PDF — malware analysis report

Static analysis result for SHA-256 de158c90f1795a2a…

MALICIOUS

PDF

75.2 KB Created: 2021-03-11 18:39:39 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-22
MD5: 8b2d212c1b619c245417d60395024adb SHA-1: f323cb2b0f1a04e3eedd77bc5ca7714d1114e334 SHA-256: de158c90f1795a2ab8436816a3d627721adfc31945fae4ea0901863114cc4fac
186 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains a link farm with numerous external URLs, suggesting an attempt to manipulate search engine results or redirect users to potentially harmful sites. The embedded content, though largely unreadable, includes references to 'new business development process pdf' and is generated by wkhtmltopdf, a tool often used to create PDFs from web content, further supporting the link farm hypothesis.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://maypoin.ru/award?keyword=new+business+development+process+pdf PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4391024/normal_5fcd5666e0bd2.pdfIn PDF document text
    • http://memowelubi.mygamesonline.org/how_to_access_lg_tv_apps_without_remote.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4451023/normal_602429728f1e8.pdfIn PDF document text
    • https://cdn.sqhk.co/jozojijejip/RQ7TcKe/42330488961.pdfIn PDF document text
    • http://wezutoxizuwal.22web.org/59290573486.pdfIn PDF document text
    • https://cdn.sqhk.co/nijodujex/fhbo4ie/wapavinuzagodeduvoras.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4406464/normal_600b57163516e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4381094/normal_600a6f6ca908a.pdfIn PDF document text
    • http://zonuvak.medianewsonline.com/dlink_dir-890l_reset_password.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://f815f12b-539f-4060-8ed9-abd2caada31b.filesusr.com/ugd/ceb2e8_fcc3818b6ec64e4f8a1f2a45ba844ef2.pdf?index=trueIn PDF document text
    • https://e6676b24-921d-4f57-8fca-beda98688f3c.filesusr.com/ugd/144d27_4ba952abb79946a888c9c8b60ea057d9.pdf?index=trueIn PDF document text
    • https://e4034479-4ead-418b-af8c-5be8dc72bdbe.filesusr.com/ugd/1e8759_eb793b30e69045aaa4110771df747fd3.pdf?index=trueIn PDF document text
    • https://e8f98835-b194-42a5-b43f-fe2f29920dd6.filesusr.com/ugd/bf650e_168fe35037744a1eae5e55658a3feb8a.pdf?index=trueIn PDF document text
    • http://wadokeg.epizy.com/flying_birds_sound_effects_free.pdfIn PDF document text
    • https://95e354e6-8561-4e52-807b-deb85f3b5fdd.filesusr.com/ugd/ca9b0a_eaf5fc7671a7477cad60a774bf0f90de.pdf?index=trueIn PDF document text
    • https://f89b8795-a90f-4359-81e0-6309601a98d9.filesusr.com/ugd/8e7730_be49c12f4adb452ca4da8e49a5549574.pdf?index=trueIn PDF document text
    • https://47a25507-5c4f-4e73-9b7c-0c49514c8174.filesusr.com/ugd/e00bd3_94bc8f0d1d6541b8bd210e4daa9e02e8.pdf?index=trueIn PDF document text
    • http://sisufovofow.atwebpages.com/the_isis_papers_review.pdfIn PDF document text
    • http://nojikigor.myartsonline.com/wegonigaxuxojiti.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_off0000eb3e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB3E 5352 bytes
SHA-256: e91d517e184acccd86d0fd90542ac1137d2266ec61a94e1100231f5c13740910
font_01_sfnt_off0000fd79.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD79 10084 bytes
SHA-256: 239abff109239f33c7e5a523e03ba47646e1bdc6cbf9209a852f82b7fcae3aac