Malicious PDF — malware analysis report

Static analysis result for SHA-256 1f99f675eef79f63…

MALICIOUS

PDF

71.2 KB Created: 2021-03-19 05:48:55 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: c7c521157ceaa9e466716eb825697259 SHA-1: ac0e79f88ed77510588fcac30e7cd46fe2ee8862 SHA-256: 1f99f675eef79f631ef2a6991cf43f1873553c55127f7140c9416fdefc721587
96 Risk Score

Malware Insights

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

The file is identified as malicious by ClamAV and an ML classifier, with heuristics indicating the presence of an external URI. The embedded URL, 'https://kuzutuzo.ru/strik?utm_term=fundamentals+of+heat+and+mass+transfer+8th+edition+solution+manual', suggests a phishing lure related to academic materials. Although no scripts were explicitly extracted, the PDF structure and the nature of the URL point towards a social engineering attack, likely to lead to further compromise.

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://kuzutuzo.ru/strik?utm_term=fundamentals+of+heat+and+mass+transfer+8th+edition+solution+manual
    • https://static.s123-cdn-static.com/uploads/4374986/normal_6005065e76439.pdf
    • https://lurukise.weebly.com/uploads/1/3/4/4/134454795/386fef89.pdf
    • https://static.s123-cdn-static.com/uploads/4467298/normal_5ff3690d0171b.pdf
    • https://vojonabof.weebly.com/uploads/1/3/1/3/131383251/fb250.pdf
    • https://cdn-cms.f-static.net/uploads/4420037/normal_600e65e71e525.pdf
    • https://pemejugaxopuled.weebly.com/uploads/1/3/4/7/134749032/3920347.pdf
    • https://static.s123-cdn-static.com/uploads/4414489/normal_5fddc31c4db56.pdf
    • https://cdn-cms.f-static.net/uploads/4505363/normal_604cfc2c9405c.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/zetituri/71316856280.pdf
    • https://uploads.strikinglycdn.com/files/3c5b3346-c27f-47dc-b6e0-773029ae1041/how_to_use_graco_high_back_booster.pdf
    • https://s3.amazonaws.com/vonusirukete/nakizax.pdf
    • https://uploads.strikinglycdn.com/files/4fd6fbea-0d71-4b14-af03-3319a153fc2d/kamokedezupupuzuwo.pdf
    • https://uploads.strikinglycdn.com/files/6d4da938-6e80-4c81-9dd2-a2b029e17e68/how_much_is_a_first_generation_ipod_worth.pdf
    • https://s3.amazonaws.com/kefiperizonofu/chaalbaaz_bengali_movie_480p.pdf
    • https://uploads.strikinglycdn.com/files/d350fe6b-2037-436b-a45e-fad12d1e754c/58590444718.pdf
    • https://uploads.strikinglycdn.com/files/7b1a1911-ad1d-4962-8352-0571e6402ad9/how_many_hours_a_week_do_you_need_to_work_at_starbucks_to_get_benefits.pdf
    • https://uploads.strikinglycdn.com/files/f76b3068-fa97-45e6-b8f0-052e3794c6df/science_process_skills_worksheets_grade_7.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d638.bin
6df3a5160cec845e3146f06491f426c8d6e8121005677515ffbaecd686d76664
pdf-font-stream PDF embedded font (sfnt) at offset 0xD638 5296 bytes
font_01_sfnt_off0000e811.bin
1c3f10cb5b38bd11df6d0259a919b078d36ef256a00d64104b78f804840ded45
pdf-font-stream PDF embedded font (sfnt) at offset 0xE811 10936 bytes