Malicious PDF — malware analysis report

Static analysis result for SHA-256 ca4cf3993184cda4…

MALICIOUS

PDF

81.3 KB Created: 2021-09-19 19:05:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: c1bfcf425a4b52597966daa755b3672b SHA-1: 6b3c160d04d2e6cf8882919aecc0cef421c0c322 SHA-256: ca4cf3993184cda4cdcdb13c4efa87ac5d6755f7431866a6e54fb7f158f65f07
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs pointing to external domains, suggesting a phishing or malware distribution campaign. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a deliberate attempt to create a large number of links on disposable hosting, reinforcing the malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 https://oniceh.ru/uplcv?utm_term=after+book+series+free+pdf+download PDF link annotation
    • http://ghettaetamionarchitetti.it/userfiles/files/20877409050.pdfIn PDF document text
    • http://rdmsrl.it/userfiles/files/zuxogovizavep.pdfIn PDF document text
    • http://azbuka-d.ru/ckfinder/userfiles/files/tupawarosulitowuribid.pdfIn PDF document text
    • https://huaienclinic.com/uploadpic/files/buzok.pdfIn PDF document text
    • http://srs-budapest.hu/uploads/files/21977838572.pdfIn PDF document text
    • http://westhollywood.ilovepokebar.com/uploads/files/xinofawaxutefeganegigi.pdfIn PDF document text
    • https://sapthagireesyathra.com/userfiles/file/5462173960.pdfIn PDF document text
    • http://e-pisanie-prac.pl/famprojekt_z_serwera/images/file/36532744649.pdfIn PDF document text
    • http://nexxstep.nl/userfiles/file/robukepopilufero.pdfIn PDF document text
    • http://xn--m1age8bh.xn--p1ai/files/file/66397463771.pdfIn PDF document text
    • https://client-sms.com/ckfinder/userfiles/files/wajodekegepalimifusomaf.pdfIn PDF document text
    • http://www.gpe-el.pro/ckfinder/userfiles/files/72434632919.pdfIn PDF document text
    • http://vandientuchinhhang.com/upload/files/ludijozuduvamapazu.pdfIn PDF document text
    • http://masterref.ru/editorfiles/file/62605945028.pdfIn PDF document text
    • http://montazerangroup.com/uploader/file/26914768288.pdfIn PDF document text
    • http://afslab.asia/upload/files/numeto.pdfIn PDF document text
    • https://movingalpsfoundation.ch/userfiles/file/37277921280.pdfIn PDF document text
    • http://kimsanghun.com/upload/userfiles/file/2021972237409193.pdfIn PDF document text
    • https://www.sharpeningfactory.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614703d6737f3---44242087796.pdfIn PDF document text
    • http://ngocphuocjsc.com/public/default/ckeditor/files/sixedimukirovafunemekuz.pdfIn PDF document text
    • https://nomortiga.com/contents/files/39043927988.pdfIn PDF document text
    • http://bloomx.com/sites/all/sites/bloomx.com/files/wisirazediropome.pdfIn PDF document text
    • http://imobilestore.de/userfiles/file/lotumawabajamululiled.pdfIn PDF document text
    • https://wscnaturalhealings.com/wp-content/plugins/super-forms/uploads/php/files/72b857e84479960dae9d86a766ed5569/pomiguzeko.pdfIn PDF document text
    • http://elpijisystem.com/file/14932431484.pdfIn PDF document text
    • 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_off0000d7a1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7A1 17940 bytes
SHA-256: 2606adf3f428ce9e625cc62525a1c9ded90e42b2f9a50b027a2bb8d87e717650
font_01_sfnt_off00010649.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10649 10792 bytes
SHA-256: 4bec735ab6efb069d87c51d8717841ec8c57794eb96e399860ed76a1f986f0c4
font_02_sfnt_off00011f24.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F24 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1