Malicious PDF — malware analysis report

Static analysis result for SHA-256 5cf0e4bc36cd9628…

MALICIOUS

PDF

72.7 KB Created: 2021-06-11 01:07:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-23
MD5: 7cb8b15480c530e1ee9ef1aef21d4f0e SHA-1: 53c47cb3f7ae5563c332177f60b673c274545601 SHA-256: 5cf0e4bc36cd96284ea5c40ff1c37a97654b1f5e2f22a5b9fd212645c7f68361
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF document was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. It contains numerous links pointing to compromised WordPress sites and disposable hosting, suggesting a link farm designed to redirect users to malicious content. The document body, though heavily obfuscated, contains references to 'wkhtmltopdf' and 'Qt', indicating it was likely generated by a tool rather than being a legitimate document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • 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.
  • 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://cructi.ru/uplcv?utm_term=excel+general+ledger+template+with+debits+and+credits PDF link annotation
    • https://cor.org.ar/wp-content/plugins/super-forms/uploads/php/files/q1i7gn8ofkugh8uk474kqpeo5f/sipulanelimenonisodaveve.pdfIn PDF document text
    • https://amartzon.store/wp-content/plugins/super-forms/uploads/php/files/48c2966a353595809860dc976f30d1c2/554626743.pdfIn PDF document text
    • http://roland-toys.eu/userfiles/file/delunawokuse.pdfIn PDF document text
    • https://eyestech.in/wp-content/plugins/super-forms/uploads/php/files/1as769uq84ctc1dmtiebd12k8r/73471608617.pdfIn PDF document text
    • http://www.tif.cn/wp-content/plugins/super-forms/uploads/php/files/6sekhvrc02qo4vbpl6ocnshfbj/69974470324.pdfIn PDF document text
    • http://meadescafe.com/userfiles/file/17816169514.pdfIn PDF document text
    • http://mmdplus.com/userfiles/files/20210530_000645.pdfIn PDF document text
    • https://fiambreszav.com/wp-content/plugins/super-forms/uploads/php/files/42c8f2f6789976e4fa79850fef976d67/nabosede.pdfIn PDF document text
    • https://betalinktech.com/blmedia/file/57547894971.pdfIn PDF document text
    • http://broadviewlibrary.org/uploaded_bvlib/file/10307391392.pdfIn PDF document text
    • https://relleno-acidohialuronico.com/wp-content/plugins/super-forms/uploads/php/files/d48ad6761e0e917fc41556d311688337/9651627856.pdfIn PDF document text
    • https://popa.com.br/wp-content/plugins/super-forms/uploads/php/files/e81c6c674109158c0de0e08592d759c1/fanesemek.pdfIn PDF document text
    • https://sakitonus.ru/wp-content/plugins/super-forms/uploads/php/files/9e93a21e58e37641038c107e3c71c1d9/zerovejedituruja.pdfIn PDF document text
    • http://www.gradur.ba/wp-content/plugins/formcraft/file-upload/server/content/files/1608dca1435fd5---26305242451.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607da956e1011---87521020725.pdfIn PDF document text
    • https://www.die-umzugsfabrik.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085200ea1fdf---95053485117.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000df3a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF3A 5744 bytes
SHA-256: dde7f3e2f128c9f3b9b1430cafbf419834436cae7e503e25557f560234360e75
font_01_sfnt_off0000f2ac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2AC 10212 bytes
SHA-256: 22253fe6eb01c8b9844775dff5b9970e9c592fa6ab2847e58e63f5e32338a1ec