Malicious PDF — malware analysis report

Static analysis result for SHA-256 e9386af1dbcf8b03…

MALICIOUS

PDF

76.5 KB Created: 2021-06-24 07:56:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-02
MD5: d2dc08f3efd499a2f3f79daf12fa6a22 SHA-1: 37fc28b1da4da1891a358351a5f3cdd1656638b1 SHA-256: e9386af1dbcf8b0385a588ad91da35f5251579029f656f76d97b7f4ad7703525
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories and presents a deceptive download button. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://stalmost.pl/userfiles/file/vuzobepakofunibixevoxuv.pdf In PDF document text
    • https://www.c2commercial.com/wp-content/plugins/super-forms/uploads/php/files/230b30ade53456a7f24ebfbaeaeeee7f/wuwibibivivakemok.pdfIn PDF document text
    • http://www.supercarrentalsofmiami.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607dab02d02c5---36063329888.pdfIn PDF document text
    • http://liubeauty.com/luutru/files/nagowa.pdfIn PDF document text
    • https://saraelv.no/wp-content/plugins/formcraft/file-upload/server/content/files/160ac711039334---kokepadamamobu.pdfIn PDF document text
    • http://jeugdopdewetenschapsagenda.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160b42a4815470---wevomezopexedolov.pdfIn PDF document text
    • http://crosswaysrecruitment.com/userfiles/file/6548800203.pdfIn PDF document text
    • http://lasfyy.com/uploadfile/file/20210601225217601.pdfIn PDF document text
    • https://juhaszautovill.hu/userfiles/file/susapojiduzerubono.pdfIn PDF document text
    • https://pyhm.ca/wp-content/plugins/super-forms/uploads/php/files/6e8tkgu0s6ugoi4snjbm8p8eul/dajumali.pdfIn PDF document text
    • https://www.paparazzirestaurant.com.au/wp-content/plugins/super-forms/uploads/php/files/af673e85fa5f3f1bee45118efb044c9f/fibotozesiwixat.pdfIn PDF document text
    • https://bem-sa.com/img/file/jijotelozifus.pdfIn PDF document text
    • http://safires.cz/ckfinder/userfiles/files/32340707583.pdfIn PDF document text
    • http://apvn.info/userfiles/file/bizexuburewavaka.pdfIn PDF document text
    • https://www.sidertest.it/wp-content/plugins/formcraft/file-upload/server/content/files/1608560121dcc8---winujozozil.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=how+can+i+split+pdf+pages+online+for+freePDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d70d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD70D 5164 bytes
SHA-256: c901538046bc1a6816ed8da8224b176e96a0f2952932215dc4a9eca891516564
font_01_sfnt_off0000e8b4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8B4 19184 bytes
SHA-256: d6284ad58bd230fd2d925fcae0f871723996bff1894ebaaae211dcbd9f08bf7a
font_02_sfnt_off0001168d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1168D 4324 bytes
SHA-256: 05d2457133b820fa77aa358e30e9acfbad3f04c46ced9a37296d9311117db176