Malicious PDF — malware analysis report

Static analysis result for SHA-256 61c4b91b3c6053e5…

MALICIOUS

PDF

75.5 KB Created: 2021-06-18 14:21:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-22
MD5: 6f9bfdd07f03c9e9405aef2cddc7543e SHA-1: 1aab2897863280b9a76c89df443558f6c3dd69ef SHA-256: 61c4b91b3c6053e51592e253b6c8e08ebf7166008f49f0863a14d5d5af83e293
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1105 Ingress Tool Transfer

The PDF contains numerous links pointing to other PDF files hosted on compromised WordPress sites, indicating a link farm designed to distribute malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware delivery. No scripts were extracted, but the structure and URL patterns are indicative of a multi-stage attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://totalfinance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160a9f776036ff---guzokeribadaliru.pdf In PDF document text
    • http://sjhrz.com/images/upload/File/25726341925.pdfIn PDF document text
    • http://lovesushiscv.com/uploads/files/95187377312.pdfIn PDF document text
    • http://plafondchauffant.fr//img/user/file/13964456212.pdfIn PDF document text
    • http://txextremecarts.com/userfiles/file/xapedu.pdfIn PDF document text
    • http://vienkiemis.lt/app/webroot/uploads/userfiles/files/88861654187.pdfIn PDF document text
    • https://www.partyshuttlebus.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607cf8f40dcfa---puvagepodotupebadopumexiw.pdfIn PDF document text
    • https://fmpride.com/wp-content/plugins/super-forms/uploads/php/files/2b7094b72bada7f06766fa3393556381/dodowekele.pdfIn PDF document text
    • https://extremetour74.ru/wp-content/plugins/super-forms/uploads/php/files/963f044cb3b0ae81d3bb8d2524247b77/zajajebabebise.pdfIn PDF document text
    • http://www.olympussverige.se/wp-content/plugins/super-forms/uploads/php/files/0pulqqhmjeg5oq74j5avj087cn/rosimetaji.pdfIn PDF document text
    • https://www.tonygssoulfood.com/wp-content/plugins/super-forms/uploads/php/files/f4e3b8d7fc4183ed89c485486da7e80d/23616000001.pdfIn PDF document text
    • https://www.numberoneporthill.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1609dfbd6d5c79---jivowiw.pdfIn PDF document text
    • http://armanetti.com/images/89481727898.pdfIn PDF document text
    • http://discoveryenglish.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a107cfd394c---nagabum.pdfIn PDF document text
    • http://yossy.biz/userfiles/file/15291459808.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=bsc+chemistry+1st+year+syllabusPDF 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
    • https://savannah.gnu.org/projects/freefont/In PDF document text
    • http://www.gnu.org/licenses/In PDF document text
    • http://www.gnu.org/copyleft/gpl.htmlIn 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_off0000da29.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA29 6744 bytes
SHA-256: b29f9350a720d2da9dc50567d08c4a82684db1fcb28a47e3a5788345b392d808
font_01_sfnt_off0000eb0e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB0E 5384 bytes
SHA-256: 53e393a11593b45a499f178d89f76f966b4660252d0d33eb5dfe4dcd5910ee2c
font_02_sfnt_off0000fd3f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD3F 10348 bytes
SHA-256: 275455e85e00755b345ecb4e9f1056a43c88ef5b1e29fb99fd6ba9650be80b7f