Malicious PDF — malware analysis report

Static analysis result for SHA-256 ae58761e2f7b4856…

MALICIOUS

PDF

82.4 KB Created: 2021-09-15 14:22:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: c6187707a01dc2ec245e890beb9061cb SHA-1: e1b4ef7e2ae97a40c5ddc74eccb5ffcbb52fde79 SHA-256: ae58761e2f7b4856e10b04bec33aa941cdbbca8e8f125b430a1fe137cd051590
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF was flagged by ML classifiers and ClamAV as malicious, with heuristics indicating it functions as a link farm. Numerous embedded URLs point to PDF files hosted on various domains, suggesting a coordinated effort to distribute content or redirect users. The presence of a disposable link farm heuristic further supports the malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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 http://dighakanchaninternational.com/FCKeditor/file/zebaliduzurizoditikiwo.pdf In PDF document text
    • http://westhollywood.ilovepokebar.com/uploads/files/36262235678.pdfIn PDF document text
    • http://okmarin.ru/userfiles/file/84936679215.pdfIn PDF document text
    • http://zoldjogsi.hu/uploads/files/ketebarixutekegus.pdfIn PDF document text
    • http://www.mostex.sk/files/articles/file/pebakokexupef.pdfIn PDF document text
    • http://hyundaidongdo3s.com/images/files/dufomajukedo.pdfIn PDF document text
    • https://kurek-rowery.pl/user_pict/file/473762972.pdfIn PDF document text
    • https://onderdurdu.com/upload/ckfinder/files/16021934708.pdfIn PDF document text
    • http://mamaskitchenorder.com/uploads/files/vatetekilor.pdfIn PDF document text
    • http://www.sintsprev-ms.org.br/ckfinder/userfiles/files/33267904339.pdfIn PDF document text
    • http://cleanking.net/userData/board/file/vuvakigedixub.pdfIn PDF document text
    • http://agataklimowska.pl/userfiles/file/41756922714.pdfIn PDF document text
    • http://divapharma.com/uploaded/file/losuregidirosifavar.pdfIn PDF document text
    • https://www.seblocation.com/ckfinder/userfiles/files/nafulalivituze.pdfIn PDF document text
    • https://nutritie-metabolism-sanatate.ro/app/webroot/files/userfiles/files/53299694181.pdfIn PDF document text
    • http://thietbiotoviet.com/Images_upload/files/sugikuvixadedere.pdfIn PDF document text
    • http://imagespa.mx/wp-content/plugins/formcraft/file-upload/server/content/files/16135e6bff3fa8---67154340807.pdfIn PDF document text
    • http://ballarioarchitetti.eu/userfiles/files/80294166669.pdfIn PDF document text
    • https://orkhaconstruction.com/wp-content/plugins/super-forms/uploads/php/files/8r0qdnd55ujjparmc01e1m6ugr/98160567466.pdfIn PDF document text
    • http://kppzp.pl/userfiles/file/zelirusisuduvaga.pdfIn PDF document text
    • http://ktcz.eu/files/files/10275461019.pdfIn PDF document text
    • http://knowleangling.co.uk/ckfinder/userfiles/files/polikuvululoganal.pdfIn PDF document text
    • http://plise.org/userfiles/file/lofamunumemapi.pdfIn PDF document text
    • http://bcslaw.hu/admin/fck_upload/file/rakoboketepepafigowoxi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=android+11+bubblesPDF link annotation
    • 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e199.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE199 10256 bytes
SHA-256: 47ebc382e3f4de5a315af7c7d8824467f69e15f62017d5fbd2956d098e75c2ea
font_01_sfnt_off0000f8c2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8C2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000110d4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110D4 16976 bytes
SHA-256: ff35ad7694b450a7ef41665c684e46798b43343c302794d418c4af1c4ea64c8e