Malicious PDF — malware analysis report

Static analysis result for SHA-256 9136c2dcd785c568…

MALICIOUS

PDF

85.0 KB Created: 2021-10-09 05:06:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 25e11ed9e2e79daca85cdd500d31ed33 SHA-1: 05a9614236cfc9038e232804a8172af7b179a65f SHA-256: 9136c2dcd785c568ee8ea83b4dba1ffcb5399479254ddde6144014724bc7386e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics indicate the PDF contains a link farm pointing to compromised CMS uploads and disposable hosting, suggesting it's used to redirect users to malicious sites. While no scripts were explicitly extracted, the PDF structure and embedded URLs strongly suggest it's part of a phishing or malware distribution campaign, likely initiated via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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 https://ketchas.ru/uplcv?utm_term=statistical+inference+casella+solution PDF link annotation
    • https://batdongsandothanh.vn/luutru/files/rapakazikinixez.pdfIn PDF document text
    • http://madmojo.com/fckupload/file/69686656395.pdfIn PDF document text
    • https://skl.deindrukdemo.nl/upload/files/devigiwekubetitururir.pdfIn PDF document text
    • http://bebaldebaran.eu/userfiles/files/22760277615.pdfIn PDF document text
    • http://localhomesales.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16144642d23cdc---66204916574.pdfIn PDF document text
    • https://morabia.fi/images/file/vejexapuregajitarevadon.pdfIn PDF document text
    • https://kaktutzhit.by/uploads/files/13424214416.pdfIn PDF document text
    • http://aloeverajuice.cz/files/file/62339218845.pdfIn PDF document text
    • http://www.jindatunnel.com/up_files/file/napizozanolafuwib.pdfIn PDF document text
    • https://zlatartopalovic.rs/files/43012775280.pdfIn PDF document text
    • https://www.truesdalepainting.com/wp-content/plugins/formcraft/file-upload/server/content/files/161496ed402ae6---tonireke.pdfIn PDF document text
    • https://nceptionsolutions.com/wp-content/plugins/super-forms/uploads/php/files/2b766f19df9c072e1c5d99d00d7ca852/79667921990.pdfIn PDF document text
    • https://jimsdelibrookhaven.com/demo/jimsdeli/admin/userfilesfile/vokobudugazupag.pdfIn PDF document text
    • https://thietbivesinhsonhoa.com/webroot/img/files/99560248642.pdfIn PDF document text
    • http://cansuyu.org/resimler/files/39985637464.pdfIn PDF document text
    • http://lotusromeo.fr/app/webroot/files/userfiles/files/50614051527.pdfIn PDF document text
    • http://satyavnetworks.com/fck_upload_images/file/bawoniw.pdfIn PDF document text
    • https://mmagame.com/userfiles/file/ranogapotifikol.pdfIn PDF document text
    • http://taxfreepoint.com/file/95456920511.pdfIn PDF document text
    • http://arnoldbolingbroke.com/ckfinder/userfiles/files/kabalotatirexa.pdfIn PDF document text
    • http://www.immiflex.com/wp-content/plugins/formcraft/file-upload/server/content/files/161353c0d60d19---sabawe.pdfIn PDF document text
    • http://expertworker.paraleumarian.ro/app/webroot/files/userfiles/files/46801355508.pdfIn PDF document text
    • https://easyown.ddproperty.com/datas/files/72547968412.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_off0000e12b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE12B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f942.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF942 10504 bytes
SHA-256: dc81320af2371d932e355029eedc658f89735baf6936d02a8fadb33c370cffd4
font_02_sfnt_off0001113a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1113A 20144 bytes
SHA-256: 08ea8ed4518fec2961fd41971fe3481fb3857ef4b86ef62c0b5f62a427f9b15e