Malicious PDF — malware analysis report

Static analysis result for SHA-256 91ef58eb6c58f53b…

MALICIOUS

PDF

81.5 KB Created: 2021-06-11 17:02:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: a38dec2af2f4802c2bef02f59e77a952 SHA-1: 0471257c5f59d9e65995ba47055407baf9f6fbe5 SHA-256: 91ef58eb6c58f53bd479d2fd897c0f88981f2a72ef8a822524632e58bb8c4716
126 Risk Score

Malware Insights

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

The PDF file was flagged as malicious by ML classifiers and ClamAV, indicating a phishing or trojan payload. It contains numerous embedded URLs, with one prominent URL pointing to a domain that appears to be a redirector for search terms like 'viktor grebennikov book pdf'. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' suggests the PDF is designed to host many links, potentially for SEO manipulation or to distribute various malicious files. No scripts were extracted, but the overall structure and URL usage point towards a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

Heuristics 5

  • 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.
  • 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://pixomot.ru/pbw?utm_term=viktor+grebennikov+book+pdf PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4377697/normal_5fd963535adb5.pdfIn PDF document text
    • https://static.s123-cdn-static-d.com/uploads/4379726/normal_60b0728e5658b.pdfIn PDF document text
    • https://molavose.weebly.com/uploads/1/3/5/3/135350427/814ebac59e26aac.pdfIn PDF document text
    • https://venubitolaxi.weebly.com/uploads/1/3/4/3/134372432/2b4cfca2fb569.pdfIn PDF document text
    • https://nurojitare.weebly.com/uploads/1/3/2/6/132682966/430043.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4375070/normal_6010a753a5eb7.pdfIn PDF document text
    • https://pepotojil.weebly.com/uploads/1/3/4/9/134900045/zexejarifafisuz_newod.pdfIn PDF document text
    • https://razizarapijesi.weebly.com/uploads/1/3/4/6/134640591/zenadazodow-piximeravasux-xadaxibenelo.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://poxanoralanu.pbworks.com/w/file/fetch/144426675/water_footprint_calculator_worksheet_answers.pdfIn PDF document text
    • http://nusometa.pbworks.com/f/sizolonogavosa.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/133478aa-1c00-41fb-b21d-f1a4cf20d1b4/kaba_electronic_lock_instructions.pdfIn PDF document text
    • http://tirotibixup.pbworks.com/f/minecraft_rtx_apk_download.pdfIn PDF document text
    • http://gujavitax.pbworks.com/f/maths_board_paper_2021_class_12_solutions.pdfIn PDF document text
    • http://fosirodovo.pbworks.com/w/file/fetch/144979629/debussy_syrinx_sheet_music.pdfIn PDF document text
    • http://ririgifavem.pbworks.com/f/resident_evil_4_hack_pc_download.pdfIn PDF document text
    • http://fatakalewene.pbworks.com/f/fegogekes.pdfIn PDF document text
    • http://xobapotowi.pbworks.com/w/file/fetch/144785817/teoria_de_la_inteligencia_multiple_howard_gardner.pdfIn PDF document text
    • http://ziriwuru.pbworks.com/w/file/fetch/144598329/dinaderinesemunomupafoja.pdfIn PDF document text
    • http://xizalow.pbworks.com/f/57267076048.pdfIn PDF document text
    • http://nusuwoxub.pbworks.com/w/file/fetch/144426978/97737793848.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/30aedb6a-6c0c-468f-90da-36371e83f2f6/pokemon_story_books_to_read_online.pdfIn PDF document text
    • http://wufamazajo.pbworks.com/f/rozagudanujoxip.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1d61eafe-9ab2-41bc-9de1-0ef4a83a74c9/vifalezi.pdfIn PDF document text
    • http://niwomif.pbworks.com/f/what_is_dua_e_qunoot.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_off00010242.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10242 5020 bytes
SHA-256: b03ea79efbc8bc847d72f29cb315bfefc08408c9608d35e2f60c933989a43ebd
font_01_sfnt_off00011378.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11378 10884 bytes
SHA-256: a89569beb469fa706d7199a13656f8d391a095ac112284519b70223e9e44ce69