Malicious PDF — malware analysis report

Static analysis result for SHA-256 522140993ca63292…

MALICIOUS

PDF

77.8 KB Created: 2021-10-01 18:32:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: b88187204d183919c08a17d9bdf288a2 SHA-1: 6194b2d8030e9aa2ab08366909f86e964de0c2ae SHA-256: 522140993ca632922920872c1209360a7e72c3507062cff0340c15726fb713e1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, pointing to multiple compromised CMS upload locations and disposable hosting sites. The embedded URLs, such as http://skuplaptop.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16144e36786991---77461892657.pdf, are likely used to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9943

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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 http://fulico.com/v15/Upload/file/202110160306714.pdf In PDF document text
    • http://sola-brothers.com/userfiles/file/58099457660.pdfIn PDF document text
    • http://landonintergroup.com/ckfinder/userfiles/files/zagalesuwosufetem.pdfIn PDF document text
    • http://hart-metale.pl/gimnazjum/userfiles/file/21526975721.pdfIn PDF document text
    • https://insinkerator.us/images/uploaded/file/junasiluzojedopetapima.pdfIn PDF document text
    • http://standardamulet.com/files/files/josabexuxabivumenilaxo.pdfIn PDF document text
    • http://www.caribbeandentist.com/wp-content/plugins/formcraft/file-upload/server/content/files/16156ff8900979---rakabugo.pdfIn PDF document text
    • http://mauchlineware.com/html/chapelstreet/web/userfiles/files/68386514097.pdfIn PDF document text
    • https://egokituz.org/files/galeria/files/dogorisinuzonekisegupudi.pdfIn PDF document text
    • https://heatingboiler.ca/fck_upload/file/24915338600.pdfIn PDF document text
    • http://www.kinoimaging.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613e5dcb6cb96---53061254768.pdfIn PDF document text
    • https://www.psk.com.au/application/third_party/ckfinder/userfiles/files/48947158640.pdfIn PDF document text
    • https://www.pelicanfinancialnetwork.com/ckfinder/userfiles/files/bejomofepiwumilelalixaf.pdfIn PDF document text
    • http://hindustanadvancedsolution.com/t/tutorfirm/uploads/ck/files/2003635654.pdfIn PDF document text
    • https://webmenuplus.com/images/file/tivironuwilejusogadevuved.pdfIn PDF document text
    • http://pnktools-th.org/ckfinder/userfiles/files/diranegakunijopemo.pdfIn PDF document text
    • http://skuplaptop.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16144e36786991---77461892657.pdfIn PDF document text
    • https://notofthisgalaxy.com/wp-content/plugins/super-forms/uploads/php/files/ieohu31asr2ev3gja9544t4fb4/71790528745.pdfIn PDF document text
    • http://kitpaisal.com/mypicture/file/medelowubuginirotomilor.pdfIn PDF document text
    • https://monyetmesum.com/contents/files/fepowovakite.pdfIn PDF document text
    • http://www.ashtralmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/16146f90750612---maxumirupukapas.pdfIn PDF document text
    • http://mama-care.com/UserFiles/file/85415944446.pdfIn PDF document text
    • http://vucert.vn/uploads/files/79116345988.pdfIn PDF document text
    • http://shceping.com/upFile/photos/2021-9/file/vasuvej.pdfIn PDF document text
    • http://chornakorn-packing.com/ckfinder/userfiles/files/bizugejijegegukidagago.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=how+to+hack+pokemon+go+in+androidPDF 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_off0000c549.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC549 19528 bytes
SHA-256: 0e70365351ecd2056ad7be354b23fde56497e0be7326e448887eb80e99d9d1c0
font_01_sfnt_off0000f88c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF88C 10916 bytes
SHA-256: 78f501c49d8438f4dd7844bf24bfb9307d8e7437c3c813e468d3a640e4785370
font_02_sfnt_off00011175.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11175 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1