Malicious PDF — malware analysis report

Static analysis result for SHA-256 3a4aa69fa7421cb9…

MALICIOUS

PDF

85.8 KB Created: 2021-09-10 12:59:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: b5d0237503a5243adf518bceca6f5de5 SHA-1: a6712570a6daeeae81d710f697b09c18807e84d2 SHA-256: 3a4aa69fa7421cb9b304ff6e284d5adc22c82e627ed6b272deef0935ccff44e4
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external URIs, with the heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicating a high likelihood of malicious intent. The ML classifier and ClamAV detection further support this, flagging the file as malicious. While no scripts were explicitly extracted, the presence of embedded URLs and the nature of the heuristics suggest the document is designed to redirect users to potentially harmful websites, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9765

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://ketchas.ru/uplcv?utm_term=so+not+worth+it+watch+online PDF link annotation
    • https://weeb.nu/userfiles/file/43910894380.pdfIn PDF document text
    • https://agsposure.org/wp-content/plugins/super-forms/uploads/php/files/1f812731d9a706d06964add11cc7d80b/64946919144.pdfIn PDF document text
    • http://stopasbestos.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1613554427e247---zalogutoxuduvomikuleren.pdfIn PDF document text
    • https://europacreativaeuskadi.eu/files/galeria/files/31416547501.pdfIn PDF document text
    • http://polyacer-ecp.com/userfiles/files/20210909_191550.pdfIn PDF document text
    • http://ipsaix.com/ckeditor/ckfinder/userfiles/files/pejawimiropij.pdfIn PDF document text
    • http://biemmecommerciale.eu/userfiles/files/diwojizorifomal.pdfIn PDF document text
    • http://tokyoto.pl/UserFiles/file/57801069787.pdfIn PDF document text
    • http://sangtaoad.com/uploads/userfiles/file/96504989442.pdfIn PDF document text
    • https://thehouseconcert.com/ckfinder/userfiles/files/zexuluxuv.pdfIn PDF document text
    • http://faradbox.pl/files/file/53003561820.pdfIn PDF document text
    • http://studioingegneriavaragnolo.com/userfiles/files/fotipajoselolezomomopa.pdfIn PDF document text
    • http://saopauloairporttransfers.com/ckfinder/userfiles/files/purenuxapitatugovekuf.pdfIn PDF document text
    • http://machinegroup.ru/img/outer/files/winivitelawiwuf.pdfIn PDF document text
    • http://www.darvidproperty.com/news/file/zekovozugupe.pdfIn PDF document text
    • http://stonestudio.pl/files/upload/file/sodututogimol.pdfIn PDF document text
    • http://www.tobywells.org/media/fckdir/file/17395654939.pdfIn PDF document text
    • http://goldmustang.com/files/files/96685865572.pdfIn PDF document text
    • https://handinhand-daycare.com/ckfinder/userfiles/files/gutumubonijobi.pdfIn PDF document text
    • http://kamakuralosgatos.com/uploads/files/3856065239.pdfIn PDF document text
    • http://mijn-nederland.nl/userfiles/file/rezowofokimo.pdfIn PDF document text
    • http://findusafranchise.com/files/files/dofesapunupu.pdfIn PDF document text
    • https://red-adlay.com/upload/files/jinovejag.pdfIn PDF document text
    • http://epoptavky.com/is/images/FCKeditor/File/88042053649.pdfIn PDF document text
    • http://myblindz.com/fck_user_files/file/lawenexipofubuk.pdfIn PDF document text
    • http://garant-fond.ru/ckeditor/ckfinder/userfiles/Images/files/60184568194.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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ca14.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA14 22584 bytes
SHA-256: efb6d67b4839c86d720c4b5bc5a9b9c21cf61159a836b172d1340604d1ddb574
font_01_sfnt_off000103df.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103DF 16232 bytes
SHA-256: 14912da01dff723b7534cdc3750a338cbf21c4a37ea4c8879de34810afc2e160
font_02_sfnt_off000119cb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x119CB 10320 bytes
SHA-256: d56237b95378ae90878ec29e8f2cb251ed2ba472d56c2ab7b944b5c8ee612d61
font_03_sfnt_off00013111.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13111 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1