Malicious PDF — malware analysis report

Static analysis result for SHA-256 81b69134afd4a7f4…

MALICIOUS

PDF

66.2 KB Created: 2021-01-03 12:20:32 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-27
MD5: ed271014626b99b119f296258b4b6476 SHA-1: b9eaba8edb844d3e74ac5d89f8c329051412a806 SHA-256: 81b69134afd4a7f4694e9b899d3316a7532c2989fb47a01b51fec0c4d2eb3db9
96 Risk Score

Malware Insights

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

The file is a PDF containing an embedded URL that points to a suspicious domain, identified by heuristics as potentially malicious and flagged by a machine learning classifier. The ClamAV detection further confirms its malicious nature, specifically classifying it as a phishing trojan. The document body, though heavily obfuscated, contains references to 'wkhtmltopdf' and a date, suggesting it might be a generated document used as a lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 4

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://trafffi.ru/123?utm_term=bowditch+volume+2+1981+pdf PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4408343/normal_5f92a8b8b93c2.pdfIn PDF document text
    • https://cdn.sqhk.co/zawitagevute/aii0hg2/facts_you_should_know_about_your_significant_other.pdfIn PDF document text
    • https://cdn.sqhk.co/moxofudifafi/sijicz0/super_sniper_game_download.pdfIn PDF document text
    • https://cdn.sqhk.co/xumobopore/djcjjF8/music_player_bass_booster_pro_apk.pdfIn PDF document text
    • https://cdn.sqhk.co/sepetoxofaw/jggexSf/47539434935.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4427793/normal_5fe20a0080140.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/7931936f-2bce-40a2-8ecc-71d35b72424d/pokemon_x_male_reader_harem_wattpad.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/892cf488-d399-4d41-8424-75a7e43062ad/lukagobupetufi.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/fbeaa745-e301-43e5-bf59-e398b519b772/lixabalarafu.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0d05c52f-5035-4956-91a2-ef17460d4dd3/33320748264.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/898fbe35-09aa-4dab-8fb2-82ec64b22645/lien_release_in_spanish.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0fe2312c-aa79-4f7c-ad36-7372527375d6/vopebujowejiromomokefib.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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c327.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC327 5644 bytes
SHA-256: 318cf7e9dcaa26c3c45bd52ccbd83644e85fcc95aaacc518ff23a0caff0d8efa
font_01_sfnt_off0000d668.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD668 11152 bytes
SHA-256: c3ede7423a7f3fa2455393b80cd1b35310155d8f779c2711a1016017dc515d69