Malicious PDF — malware analysis report

Static analysis result for SHA-256 4087d09db375816f…

MALICIOUS

PDF

92.8 KB Created: 2021-09-15 13:01:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: a0e8b1799e45ba529ea951eefa5f0381 SHA-1: b91ca6ca52a64cd5cf0935e54ebfa169026cb9c8 SHA-256: 4087d09db375816f275d145084c8af54f00f0a0d33bdcd380da486964e73a5b5
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by a machine learning classifier and ClamAV as malicious, with heuristics indicating it functions as a link farm on disposable hosting. The embedded URLs, despite some being marked as benign, contribute to the overall suspicious nature. No scripts were extracted, but the PDF structure and heuristics suggest a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9915

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 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://kimdaiphatsteel.com/Images_upload/files/87568068245.pdf In PDF document text
    • http://masterkontroll.hu/ckfinder/userfiles/files/6363687887.pdfIn PDF document text
    • https://led7.ru/file/86577238630.pdfIn PDF document text
    • http://onishi-kyosendo.jp/archive/wevawigonagilov.pdfIn PDF document text
    • http://adice-area.com/pictures/files/perenegapekonamiti.pdfIn PDF document text
    • http://villa-margherita.biz/userfiles/files/68723729893.pdfIn PDF document text
    • https://morganmethod.tuesdaytrader.com/ci/userfiles/files/sitorasalokabo.pdfIn PDF document text
    • http://sakem.org/userfiles/files/matipofulasumet.pdfIn PDF document text
    • http://emilymillerlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/begavuwivodokezosuvum.pdfIn PDF document text
    • https://everywheregenes.com/uploadfile/qu26_qu106_com/files/4702986367.pdfIn PDF document text
    • https://thingstodobahrain.net/ckfinder/userfiles/files/31133427825.pdfIn PDF document text
    • http://xn--djr00fsyfv0o5qgy9u.com/filespath/files/20210913013558.pdfIn PDF document text
    • http://hypotekaprezamestnancov.sk/res/file/74794601355.pdfIn PDF document text
    • https://rugsinc.in/UserFiles/files/14028674658.pdfIn PDF document text
    • http://tienphat.vn/imagesflashupload/file/tijokikoxi.pdfIn PDF document text
    • http://www.iamgoingto1996.com/wp-content/plugins/formcraft/file-upload/server/content/files/161308260a875f---tabipafikegune.pdfIn PDF document text
    • https://ceccardolj.ro/userfiles/file/14414305339.pdfIn PDF document text
    • https://art-lamps-rali.eu/files/file/nipivefila.pdfIn PDF document text
    • https://livnica-metalurg.com/images/pages/file/terunudo.pdfIn PDF document text
    • https://madeinstlucia.com/userfiles/files/falikamif.pdfIn PDF document text
    • http://goozzl.com/userfiles/files/xuziwezasaxanepaf.pdfIn PDF document text
    • http://fertilityupdates.com/userfiles/files/dimajaroka.pdfIn PDF document text
    • http://mijneigenlift.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613024b8850fe---pugemoli.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=aot+android+by+riva+devPDF 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_off0000e5d3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5D3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fde4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDE4 16488 bytes
SHA-256: 4da335bb413b3f062754bd81c25dea521754735cc357156341da2fb2734a8572
font_02_sfnt_off000114da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x114DA 10328 bytes
SHA-256: 0985175d7ffa3a87936163261e1af5bb398d28bbe120929eef15981472f92d6d
font_03_sfnt_off00012c4d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C4D 21640 bytes
SHA-256: 2059a4e680e5ef3696f20c0a45bb1fa662077c086f049327fa729e7a96aca446