Malicious PDF — malware analysis report

Static analysis result for SHA-256 efa04aa6794588bf…

MALICIOUS

PDF

87.8 KB Created: 2021-09-21 21:59:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: c81426c41238fbbe7c4c043a6095e265 SHA-1: a2fc8d0b4b33f4916464c65eda4eca7dc668742a SHA-256: efa04aa6794588bfa8863bc98bc7bfdc3fd5593f10340cf430f4bf476db3780d
134 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, indicating a high likelihood of malicious intent. The presence of numerous external URLs, many hosted on disposable domains, suggests a link farm designed to redirect users to malicious content, likely for phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with malicious document delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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://bokaichenyu.com/upload/files/61349856374.pdf In PDF document text
    • http://oresteruggiero.com/userfiles/files/73402337983.pdfIn PDF document text
    • http://huyndaicaudien.com/upload/files/zixilekaxefubakozexolikel.pdfIn PDF document text
    • http://werkschoenenverkoop.nl/images/docman/files/88524792964.pdfIn PDF document text
    • https://learnrkbin.jugalbandiresearch.com/ckfinder/userfiles/files/28115802753.pdfIn PDF document text
    • https://cosmopolitanhotel.eu/uploads/wysiwyg/files/7154543379.pdfIn PDF document text
    • https://barrier.exma.cl/ckfinder/userfiles/files/12482616867.pdfIn PDF document text
    • https://asiantms.com/ckfinder/userfiles/files/63581165898.pdfIn PDF document text
    • http://speckletrack.com/update/editor/file/jeripakepomew.pdfIn PDF document text
    • http://sreema.org/FCKeditor/file/kibavakazakukekogov.pdfIn PDF document text
    • https://thietbivesinhsonhoa.com/webroot/img/files/gatisenab.pdfIn PDF document text
    • http://karmakonnect.org/DrumiBhatt/karmakonnect.org/Final/ckeditorimage/files/ruluviw.pdfIn PDF document text
    • http://houselandia.ru/files/didezadibojifurowemuxeko.pdfIn PDF document text
    • http://ebslang.net/_UploadFile/Images/file/48591225074.pdfIn PDF document text
    • https://greenways.at/userfiles/file/51362186354.pdfIn PDF document text
    • https://icon-studios.com/userfiles/file/11614785192.pdfIn PDF document text
    • http://xn--80aer5aza.xn--c1acndkmcarx.xn--p1ai/ckfinder/userfiles/files/17917191015.pdfIn PDF document text
    • http://lex.tj/img/file/99664581956.pdfIn PDF document text
    • https://techlan.pl/files/file/bubepogisu.pdfIn PDF document text
    • http://tongkhomica.com/upload/files/kogobiwobugad.pdfIn PDF document text
    • http://costruzionibulagna.it/userfiles/files/vebiker.pdfIn PDF document text
    • https://nanyangtextile.com/userfiles/file/65871964873.pdfIn PDF document text
    • http://edu-soft.ru/site/htmlimages/file/tafowidalorelarobotex.pdfIn PDF document text
    • https://www.ideaklinikbakirkoy.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140191bd3378---tesunadujelelozefere.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=general+knowledge+questions+and+answers+pdf+in+bengaliPDF 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_off0000f03e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF03E 11276 bytes
SHA-256: 13ea9b0ebab7126fa1d538fac217ea0cbfca37709964f09d2b9afdc9777144a0
font_01_sfnt_off00010a28.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A28 18132 bytes
SHA-256: 0818aea82b405365ed1dc83c67ff33af742ec31ac17028b2fa612914e2d9390a
font_02_sfnt_off0001395b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1395B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1