Malicious PDF — malware analysis report

Static analysis result for SHA-256 37265d225c40acde…

MALICIOUS

PDF

76.3 KB Created: 2021-04-01 22:25:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-24
MD5: d9e61190c051887b8b7aa5eb0a4bf15a SHA-1: 526bf798eab9ad801fc8a0e21ef1211a8e813e7f SHA-256: 37265d225c40acde675aeeb69440abf89fcb3e6810793937371499d1046c489e
186 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

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
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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://druttle.ru/123?utm_term=maths+worksheets+year+1+pdf PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4427529/normal_60527c686fcbf.pdfIn PDF document text
    • https://cdn.sqhk.co/nupasoxure/hLohfhd/85053270744.pdfIn PDF document text
    • https://cdn.sqhk.co/dawolesirip/hYUgfid/drawback_synonym_crossword.pdfIn PDF document text
    • https://cdn.sqhk.co/jegivoziba/ha8shjb/does_my_crush_like_me_quiz_buzzfeed.pdfIn PDF document text
    • https://cdn.sqhk.co/wakivugex/eicjj6p/shattered_pixel_dungeon_mage_guide.pdfIn PDF document text
    • https://cdn.sqhk.co/nuxarufodir/nhihfki/live_stream_catholic_mass_saturday_vigil.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4496402/normal_5fe223245acfb.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/c6d4cae9-7423-45b3-a351-f40a76b6f974/hp_spectre_x360_motherboard_problems.pdfIn PDF document text
    • https://765a5d72-5774-4a4d-a421-5c90307110ba.filesusr.com/ugd/f2a868_9a3d2b0ab2d04939b0e9fef8f21075ed.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/01b6f84c-160a-4f8e-a194-5f01bde2b22c/vopebixor.pdfIn PDF document text
    • https://85fc0914-20e3-4f1c-be8c-de7e6f89f47e.filesusr.com/ugd/a44510_cfa597e3b7eb419abe27622ae3513e69.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/bec00155-81ff-4218-bd4b-45749859fd65/cenote_chilam_balam_precio.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/638e545d-ff97-408a-9333-de9ee6af3a2a/febuxuseve.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/80b87835-3f88-4ce2-abc6-0985ae1eebb3/i_can_feel_the_left_side_of_my_brain.pdfIn PDF document text
    • https://0dd4521b-3e41-4083-9bcc-807cce03ae78.filesusr.com/ugd/cfe2e9_a362e6d4a37a4e3abf4d6710020cdf4d.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/45651009-8e67-492a-b8c2-c1ba45c9c196/gre_verbal_reasoning_practice_questions.pdfIn PDF document text
    • https://6ec3981f-6443-463b-a164-91fc69f101d9.filesusr.com/ugd/7603ae_550d61220d4144bb9a6c3f23661aaf75.pdf?index=trueIn 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_off0000ed58.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED58 5412 bytes
SHA-256: dc02f6d61df09df88f92ac825dcbdeff3158f185c88104b4ed5ac53bbd02577e
font_01_sfnt_off0000ffe6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFE6 10636 bytes
SHA-256: 242a0f566e99f38212c4715de8c4af3bbdcd43d5069ad4c04a9e97b076d5a0ae