Malicious PDF — malware analysis report

Static analysis result for SHA-256 b4f7877ef641508f…

MALICIOUS

PDF

72.9 KB Created: 2021-05-13 20:10:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-25
MD5: 21581033f7cc6c85f0dff98573c8b4aa SHA-1: 5ba2fbbe4d51a67c5de7fc81b4ffe7cf8ffaa1e9 SHA-256: b4f7877ef641508f5eb57141bdc7db265ed3567eb13a215cfcecd0433ba710c3
186 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9989

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://xajibur.ru/strik?utm_term=daily+language+review+grade+8+week+9+answer+key PDF link annotation
    • https://xaxazusilu.weebly.com/uploads/1/3/4/7/134757455/14d71fcac5c3b.pdfIn PDF document text
    • https://cdn.sqhk.co/limizolaxa/dzQig84/download_unnie_doll_mod_apk_versi_terbaru.pdfIn PDF document text
    • https://wabodaji.weebly.com/uploads/1/3/2/6/132681772/gedomufutefe.pdfIn PDF document text
    • http://jepenufi.getenjoyment.net/fozegorurapusomezoluvi.pdfIn PDF document text
    • http://ginupedarokuxu.getenjoyment.net/adjective_prepositional_phrase.pdfIn PDF document text
    • https://zuragani.weebly.com/uploads/1/3/1/4/131438510/tapakeninosume_zogami_wajizose_balosigez.pdfIn PDF document text
    • https://cdn.sqhk.co/letarezetap/iihhef5/96373328558.pdfIn PDF document text
    • https://pajuxosam.weebly.com/uploads/1/3/0/9/130968950/migofidolej.pdfIn PDF document text
    • https://wetololat.weebly.com/uploads/1/3/4/7/134710700/3053928.pdfIn PDF document text
    • https://cdn.sqhk.co/jigekuragige/erhiSjg/mad_gunz_battle_royale_fps_online.pdfIn PDF document text
    • https://jenogadagebaz.weebly.com/uploads/1/3/4/5/134586404/tasekusoveriwa.pdfIn PDF document text
    • http://fafijitesulexiz.mygamesonline.org/air_operated_double_diaphragm_pump.pdfIn PDF document text
    • https://misodewegakev.weebly.com/uploads/1/3/4/7/134717908/reladumojaxitelizemi.pdfIn PDF document text
    • https://jedunifoxawixe.weebly.com/uploads/1/3/4/4/134458330/eda5877e80f.pdfIn PDF document text
    • http://zuvatewovu.scienceontheweb.net/nios_assignment_cover_page_file.pdfIn PDF document text
    • https://pusenosate.weebly.com/uploads/1/3/5/3/135347115/2175903.pdfIn PDF document text
    • https://cdn.sqhk.co/puwidebudojo/xgeKSeQ/9233704413.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
    • https://ac402fee-74f4-49a6-b5a4-6a03c6a057de.filesusr.com/ugd/b0cd75_71027e3939444e5380557c4886706515.pdf?index=trueIn PDF document text
    • https://12f7643e-9106-4823-89c2-0bdaecd1bc22.filesusr.com/ugd/1f6d71_92d1e72dd51b41f780bbcddb846e475f.pdf?index=trueIn PDF document text
    • https://c4e42e93-254c-4ba8-b495-737f84002742.filesusr.com/ugd/ddb60a_c31cb4e5a8104bef8f36886279684547.pdf?index=trueIn PDF document text
    • https://945b3f91-9c76-4178-be32-f0dab3cfe2c6.filesusr.com/ugd/8d5d69_9f517b69daff4485b7feac116ffd21df.pdf?index=trueIn PDF document text
    • https://949217f6-ecfc-4a1b-8806-967b2a145102.filesusr.com/ugd/b08fd2_b2a778044acd499b8340470c9abec4d5.pdf?index=trueIn PDF document text
    • https://7f993087-45f6-41f4-96e5-9dcaca18fb91.filesusr.com/ugd/9a92dd_1fec0deb3f0443f3b4ad7fd288b4438a.pdf?index=trueIn PDF document text
    • https://4be8a7ba-6c9a-47a4-99fc-a5961b41a404.filesusr.com/ugd/132250_b54ab16c9040469f98be179f7bf41934.pdf?index=trueIn PDF document text
    • https://f499a9ea-5579-4d3c-a180-ba191067f9b7.filesusr.com/ugd/34ec99_c7bf22e61cac43e2ab46a0ad7951b9dc.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000cfc9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCFC9 5352 bytes
SHA-256: 93fb1d89a7f440eafaab31bcc4642bd2193bc5c6dba7223d165daec453cf9e53
font_01_sfnt_off0000e212.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE212 11068 bytes
SHA-256: 016dfedcf7f2169377e1bc7c87edf87e9a18851d32d1c9fd009b1622cc891c87
font_02_sfnt_off000107a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107A3 4324 bytes
SHA-256: 9f355172d696dda274cac500966718f112ce76951f19577ac4888987ea6471b2