Malicious PDF — malware analysis report

Static analysis result for SHA-256 b8f25d263c34edb0…

MALICIOUS

PDF

78.1 KB Created: 2021-06-10 16:46:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-14
MD5: 7dc8a2187b0f18137a507e507019f593 SHA-1: e8f973bd893c3e6e9cb49532b52f40a4f8ce2589 SHA-256: b8f25d263c34edb09991fa94f0682a0ab74066965774ec9dd9160b09861ca12c
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan payload. It contains numerous links, many hosted on compromised WordPress sites or disposable domains, designed to appear as free downloadable graphic novels. The embedded URLs and link farm structure suggest an attempt to redirect users to malicious content or phishing sites.

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 https://chcial.ru/uplcv?utm_term=graphic+novel+pdf+free+download PDF link annotation
    • http://thingsantiquesla.com/userfiles/files/jetakabiza.pdfIn PDF document text
    • http://europeanprofservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160771cc363df9---66099094953.pdfIn PDF document text
    • https://buddingheights.org/wp-content/plugins/formcraft/file-upload/server/content/files/1609a70e554a56---vonitipa.pdfIn PDF document text
    • https://xn--80aaa1anac6cg.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/988fae5dc40224df218fd36602255ef8/88123924875.pdfIn PDF document text
    • http://winkeleninzundert.nl/uploadimages/files/67980865224.pdfIn PDF document text
    • http://sns.hu/_user/file/18456886576.pdfIn PDF document text
    • https://movesforfree.com/wp-content/plugins/super-forms/uploads/php/files/eg8sg9phpgeid8gaa6ufd4lpl2/42710372750.pdfIn PDF document text
    • https://nbtele.com/en/cache/fck_files/file/70687997308.pdfIn PDF document text
    • http://snookerfootball.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1608e53eb57c24---68077676757.pdfIn PDF document text
    • http://itaindustrial.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a2c539e4edf---liretivimubuzutubat.pdfIn PDF document text
    • https://kuechentreff-schmid.de/wp-content/plugins/super-forms/uploads/php/files/bp73fi3n9pi600nnp5l64ltlvk/guxemosewifomupejeji.pdfIn PDF document text
    • http://reanda.com/jingkelun/userfiles/files/20210607014354.pdfIn PDF document text
    • https://www.sesc.com.ua/wp-content/plugins/super-forms/uploads/php/files/26hu187c092rlpr3b3e3iv5lj1/wesenixafis.pdfIn PDF document text
    • https://forkidsvietnam.vn/wp-content/plugins/super-forms/uploads/php/files/kocuct5bvqko4beem2n1v867jk/nedepepamamafaletolikev.pdfIn PDF document text
    • https://phoenixknights.co.uk/wp-content/plugins/super-forms/uploads/php/files/a17a91073b7fd7331383fbbdb0a6ad6d/54330751325.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
    • 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_off0000e820.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE820 4956 bytes
SHA-256: b8bb36a3edc0c1e88e7cb6faa65f2551fad60a69afef517da3e12a3c62a72ed2
font_01_sfnt_off0000f900.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF900 10212 bytes
SHA-256: 82e5aa03f0fc754f00d07e200a5684e7fbbef77d3ea2c9595258481cce57e7e4
font_02_sfnt_off00011bf5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BF5 4324 bytes
SHA-256: 4fcfa7c68d76e23b667942a3ac892d2d5d88346478daafc61479ad4df4af3dd3