Malicious PDF — malware analysis report

Static analysis result for SHA-256 588107ef61ba7782…

MALICIOUS

PDF

93.5 KB Created: 2021-09-13 05:02:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 3a890012c43a944941af337a75726052 SHA-1: 48ec32edb127206c7e0a4821cb9050fd2049c6ae SHA-256: 588107ef61ba778284e06f85869342db27c56598b6789b306c281ddaf352e824
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The ML classifier and ClamAV detection strongly indicate this PDF is malicious. It contains numerous embedded URLs, many pointing to potentially disposable domains, suggesting a link farm designed to host malicious content or phishing pages. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating a tactic to obscure the true malicious destination. No scripts were extracted, but the overall structure points to a lure document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9927

Heuristics 5

  • 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 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://www.allatpatikapecs.hu/images/file/vijamusav.pdf In PDF document text
    • https://atlantidegattico.it/file/gurumuminulidonexajar.pdfIn PDF document text
    • http://www.egymast-segito.hu/uploaded/fck/file/35881634683.pdfIn PDF document text
    • http://techmechengineers.com/uploads/rawexawoduw.pdfIn PDF document text
    • https://karlschool.org/uploads/files/202109020449148498.pdfIn PDF document text
    • http://geodavidepini.it/userfiles/files/19342168499.pdfIn PDF document text
    • http://thailaundry.com/imgUpload/files/bujizu.pdfIn PDF document text
    • http://vaynhe.com/upload/files/63767179991.pdfIn PDF document text
    • http://vaynhe.com/upload/files/gumilulapelazixor.pdfIn PDF document text
    • http://nakamurasangyou.jp/app/webroot/uploads/files/sidokamapuzupesosolano.pdfIn PDF document text
    • http://sadiqandsons.com/userfiles/files/nipejivunifibebofido.pdfIn PDF document text
    • http://bascobrunswick.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1613a0fa1adfe6---sawodomafut.pdfIn PDF document text
    • http://vector-food.pl/userfiles/file/fakexabosixib.pdfIn PDF document text
    • http://bxbrdh.marketsearching.com/upload/files/gegibidifegisudebu.pdfIn PDF document text
    • http://directartdeal.com/uploaded_files/userfiles/files/tezixal.pdfIn PDF document text
    • http://cssh.es/img/file/viguzazabonegabodu.pdfIn PDF document text
    • https://my-natural-style.net/upload/files/42944175811.pdfIn PDF document text
    • http://www.hz-kontejnery.cz/ckfinder/userfiles/files/zogenumitutisuzimaba.pdfIn PDF document text
    • https://lbk-ingatlan.hu/uploads/file/tazosib.pdfIn PDF document text
    • http://thegioichuyendong.info/app/webroot/upload/files/88634240977.pdfIn PDF document text
    • https://monarchwinemerchants.com/wp-content/plugins/super-forms/uploads/php/files/86ed70575a3c1829d571a4de9b8de4b2/dufipurimirulasorode.pdfIn PDF document text
    • http://goozzl.com/userfiles/files/povukaselarazefero.pdfIn PDF document text
    • https://keongracun.org/contents/files/123693231.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=open+g+chord+chart+pdfPDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ee89.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE89 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000106a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106A0 10616 bytes
SHA-256: 238946e083419e324b92e2a71d9a4aad17bfd63a02bf290fe8e3650cff8e1ab0
font_02_sfnt_off00011ea3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11EA3 18140 bytes
SHA-256: b130c3adfee3db431432b5214387f8863b796ab7f6c542698bf405721a5853a5
font_03_sfnt_off00013a89.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13A89 17644 bytes
SHA-256: d69e0537980f3ce348623bcb04cb9b79b42d8993f793c90504ac85202791139c