Malicious PDF — malware analysis report

Static analysis result for SHA-256 8d6ab1e041da65af…

MALICIOUS

PDF

76.9 KB Created: 2021-06-04 08:40:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: d905b484e0ba1cc1218847153d63c351 SHA-1: d89ed6a8987da70c9799329d339a8380ee12151a SHA-256: 8d6ab1e041da65af6052a8f4c48fd1cb6dcf3ab887699bb5d726aecc0efd93c8
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. It contains an embedded URI pointing to a suspicious URL, 'https://krisoc.ru/pbw?utm_term=doel+sumbang+mp3+runtah', which is likely used to deliver a secondary payload or conduct phishing. The PDF structure itself appears to be intentionally malformed, indicated by duplicate object bodies, a common tactic in obfuscating malicious content.

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://krisoc.ru/pbw?utm_term=doel+sumbang+mp3+runtah
    • https://cdn-cms.f-static.net/uploads/4477630/normal_60b951e412cc9.pdf
    • https://static.s123-cdn-static.com/uploads/4465003/normal_5fe3a16320636.pdf
    • https://cdn-cms.f-static.net/uploads/4416928/normal_605c00d380c4a.pdf
    • https://cdn-cms.f-static.net/uploads/4489412/normal_5fd3b8a87a22b.pdf
    • https://cdn-cms.f-static.net/uploads/4455403/normal_6022c91bf12cf.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/30567aea-e24e-42c4-a927-aea46c0a25ea/tiburuxadoselepuno.pdf
    • https://uploads.strikinglycdn.com/files/63c97a08-b288-4e56-9fc8-eee8e4c22691/70140783833.pdf
    • https://uploads.strikinglycdn.com/files/4d33d60b-6f18-4b97-81de-70068ec8b4cc/74359674458.pdf
    • http://pulixojesu.pbworks.com/w/file/fetch/144514350/how_do_i_update_my_employment_exchange_card.pdf
    • http://fudejob.pbworks.com/w/file/fetch/144577218/vibolowewuxujabu.pdf
    • https://uploads.strikinglycdn.com/files/8e901370-6a3f-4e08-969a-38271494616a/27295111831.pdf
    • http://pojaweku.pbworks.com/w/file/fetch/144592722/como_eliminar_las_cucarachas_de_manera_natural.pdf
    • http://rorazokazog.pbworks.com/f/xoledifuvuvefanelebu.pdf
    • http://refarumiba.pbworks.com/w/file/fetch/144599634/rajulerawavijemapepizu.pdf
    • https://uploads.strikinglycdn.com/files/7a36b8c6-b1aa-4c06-929c-30e8d5727465/how_to_number_shapes_in_visio.pdf
    • https://uploads.strikinglycdn.com/files/45b09c02-9c19-4392-b6fb-1f6fc21819d8/do_xbox_live_gold_digital_codes_expire.pdf
    • http://wojipag.pbworks.com/f/74443338712.pdf
    • http://doxawadar.pbworks.com/w/file/fetch/144513195/rounding_numbers_worksheets_grade_5.pdf
    • http://lopofemusun.pbworks.com/f/warobekubavajudu.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_off0000f03b.bin
e89e5bf9ecdfbee8a19a52e14dfd9f882cb4cbde98d19996d2957b5305313aa5
pdf-font-stream PDF embedded font (sfnt) at offset 0xF03B 5536 bytes
font_01_sfnt_off000102dc.bin
43d71aa7213b5c54388b1089833156f6c98e969af53bff0e7b4daa2cb6ba82fe
pdf-font-stream PDF embedded font (sfnt) at offset 0x102DC 10896 bytes