Malicious PDF — malware analysis report

Static analysis result for SHA-256 8d21163cdbf48935…

MALICIOUS

PDF

100.4 KB Created: 2021-04-21 22:33:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: 74e4d794a5c59139e015f4570fa47f95 SHA-1: 96cac0b0d41a2ae2b472846a20acbf90d5187155 SHA-256: 8d21163cdbf48935b6b6602a5c9390b796d07c77467c2db61f3ad3fee1fc5e6c
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 0.9997

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://golowaki.ru/strik?utm_term=focusrite+scarlett+solo+2nd+gen+buffer+size PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4407994/normal_603a5b88b2a6d.pdfIn PDF document text
    • http://fomilexavekol.22web.org/fax_cover_sheet_sample.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4485689/normal_5fccdfe030fcc.pdfIn PDF document text
    • https://xomivumikeso.weebly.com/uploads/1/3/0/7/130774979/96f297120a40.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4450251/normal_6000a1dc77347.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4473645/normal_60405bbe99644.pdfIn PDF document text
    • http://simanamilorej.iblogger.org/tafsir_mimpi_islam.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4384048/normal_606957dcc30f1.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4447096/normal_5fde4f879e81e.pdfIn PDF document text
    • https://sovuzozasofebod.weebly.com/uploads/1/3/4/3/134343281/nixupejif_jupadok_lasaxinap.pdfIn PDF document text
    • https://sewemojokevapu.weebly.com/uploads/1/3/4/4/134463988/4791362.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4465252/normal_602e351a0d6af.pdfIn PDF document text
    • https://buxodofuluni.weebly.com/uploads/1/3/4/8/134875319/sowizuvukosufak-mefudines.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://45f0f727-c607-4398-b3b7-8b42e23b21b2.filesusr.com/ugd/0a84ca_ffeca197d3f242359d29d48b2269c1bc.pdf?index=trueIn PDF document text
    • https://2eda13a9-9e0f-47dd-bbfa-a9a5028a3314.filesusr.com/ugd/61c57f_810bd141e3d34dc8a68e2923e66f739a.pdf?index=trueIn PDF document text
    • https://0ca3454e-05ac-49fc-8d00-644b1af7be3c.filesusr.com/ugd/8bf3fc_f414d68df36140a7b08d529bfef85891.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/c61c6567-d136-4abc-b6ec-28fa74d288b8/ledotefo.pdfIn PDF document text
    • https://a8a70d16-e3f0-4805-b115-4d8c62c40b57.filesusr.com/ugd/82e28d_8de7cf852f6e4fb49b53f80bf26dde7a.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/84ee6d2b-44b9-409c-a30d-e3bf186f2fd5/rizozapumodifuvale.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f5704a12-45f7-489e-8f8a-871b86a7d3a1/86244457416.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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00013285.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13285 5464 bytes
SHA-256: edccfb8edb6fe67e3660a558df1fa63fb329318f8bf5ddaac5419b9632f2234b
font_01_sfnt_off00014532.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14532 12608 bytes
SHA-256: 476799ccaf069c869c90f76208fa5a2677fe66fbfb434387746ae082ac40e2a2
font_02_sfnt_off00016e93.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16E93 16120 bytes
SHA-256: 184efd0e138a9418359f6897f9ac56b5cd93cafbd57abf30711ac2aee7e18832