Malicious PDF — malware analysis report

Static analysis result for SHA-256 d23f3d3f72d9bd89…

MALICIOUS

PDF

115.6 KB Created: 2021-10-11 22:24:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 5e892e660b5e6036998cba6e955d35c7 SHA-1: 173b760c331c70178f5e33f2c992cec499d7a5d5 SHA-256: d23f3d3f72d9bd892ce0e76df699f8fc2c5ebf615adfd40fbcc6afacf6f79b44
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The ML classifier and ClamAV detection strongly indicate malicious intent. The PDF contains numerous embedded URLs, many pointing to disposable domains, suggesting a phishing or link-farming scheme. While no scripts were explicitly extracted, the presence of PDF-specific heuristics and the overall malicious verdict point towards a common PDF-based attack vector, likely involving the exploitation of a PDF viewer vulnerability or a social engineering lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 https://damiel.eu/userfiles/file/xukalixizegakoleraredaz.pdf In PDF document text
    • http://tuvantindat.com/uploads/2021-09-29/images/files/64849300543.pdfIn PDF document text
    • http://aqgwegfjdlk.handyfriendship.com/upload/files/dopuba.pdfIn PDF document text
    • https://garnet-medical.com/userfiles/files/simaxelizura.pdfIn PDF document text
    • http://pasaru.com/upload/files/jomovofulofoboninageruwab.pdfIn PDF document text
    • https://nusantarabet4d1.com/contents/files/mikerepezafosupusosut.pdfIn PDF document text
    • https://granitabrasive.com/editor_up/julogibi.pdfIn PDF document text
    • https://baxsporthorses.nl/userfiles/file/rerironuxatof.pdfIn PDF document text
    • http://aptekainternetowa.net/_mdm_apteki/file/45936103308.pdfIn PDF document text
    • http://www.qookspot.kitchen/wp-content/plugins/formcraft/file-upload/server/content/files/1615ae061d729f---vebepowomusufesafoba.pdfIn PDF document text
    • http://jamxmpharmatech.com/upload/files/29394697923.pdfIn PDF document text
    • http://knupress.com/pds/editor/file/fodikaduxaporef.pdfIn PDF document text
    • https://b2bircruise.travflex.com/bot/ckfinder/uf/files/dokiwitakimoxaso.pdfIn PDF document text
    • http://assessmentinsight.com/ckfinder/userfiles/files/50737218441.pdfIn PDF document text
    • https://karpzbeldowa.pl/uploads/userfiles/files/17469352532.pdfIn PDF document text
    • http://ampletrekking.com/userfiles/file/99411680549.pdfIn PDF document text
    • http://ros-audit.com/i/up/file/21388123507.pdfIn PDF document text
    • http://3dsami.org/uploadfilefiles/11158826369.pdfIn PDF document text
    • https://turismopontevedra.com/ckfinder/userfiles/files/zogovozixakive.pdfIn PDF document text
    • http://cesvil.it/filesUploads/file/44100530234.pdfIn PDF document text
    • http://generale-bureautique.fr/gdb/files/file/62180184113.pdfIn PDF document text
    • http://fullcolorspandoeken.nl/userfiles/file/ravosunut.pdfIn PDF document text
    • http://civicwomen.com/ckfiles/files/nejaxu.pdfIn PDF document text
    • https://rjpexport.com/files/94988483530.pdfIn PDF document text
    • http://feedproxy.google.com/~r/Xvkpad/~3/HTGXzuRVGb4/uplcv?utm_term=titus+andronicus+playPDF 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_off00015aa5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15AA5 20292 bytes
SHA-256: 9f937419655b4d3ec2d8689913529aa80ef2056aadf99bf9df1c0bc5a1f580ad
font_01_sfnt_off0001902e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1902E 10552 bytes
SHA-256: 0847eb55ffd77330a02e5f7b5ff494a3622cbd88babd1aa3b413036ab25dd784
font_02_sfnt_off0001a862.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1A862 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1