Malicious PDF — malware analysis report

Static analysis result for SHA-256 5f72b6e9c011db97…

MALICIOUS

PDF

86.9 KB Created: 2021-04-07 18:13:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: ad9d81ee0d0173e3e0d1cf4aad4ee5c2 SHA-1: d2857bc7aa9c2f74236ab6c508bcdc5476e783b5 SHA-256: 5f72b6e9c011db972fd842d8c85e905ce8c06b19614c7c063d0c5245dd928a76
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, identified as a link farm, with one suspicious URL (vilenefex.ru) flagged for potential phishing or malware distribution. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or distributing further malicious content via the embedded links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 5

  • 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.
  • 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://vilenefex.ru/123?utm_term=apocalypse+world+full+pdf
    • https://cdn-cms.f-static.net/uploads/4403683/normal_606ce3ec578a0.pdf
    • https://davovexo.weebly.com/uploads/1/3/4/3/134355956/129208.pdf
    • https://fukidupedogof.weebly.com/uploads/1/3/2/8/132814182/xidar.pdf
    • https://static.s123-cdn-static.com/uploads/4501479/normal_5ffbcc12e8da3.pdf
    • https://cdn-cms.f-static.net/uploads/4375199/normal_6056c77aa9757.pdf
    • https://cdn-cms.f-static.net/uploads/4413980/normal_603a66b92cf04.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cff07a16-13b2-455b-8a78-148a75b158b4.filesusr.com/ugd/cda0c7_65c8578df0ca4119ac489e4ac59ce8e9.pdf?index=true
    • https://0f8fedcd-12c0-4678-86f8-e2bff7269121.filesusr.com/ugd/70e7d4_514b7b40eb4145578215aa025b9d560e.pdf?index=true
    • https://b7f5b04e-b247-49a4-9dc0-39f0c843ec09.filesusr.com/ugd/b56f86_ecb0933b72364b69a031d6ffe6a50109.pdf?index=true
    • http://safamulidapi.epizy.com/anamorphic_illusion.pdf
    • https://aefb6378-f3ca-470a-b9d2-22936542d087.filesusr.com/ugd/fe129c_22e27423656b4660a487adbc1e45bdb7.pdf?index=true
    • http://navamobatetipo.rf.gd/52182490522.pdf
    • https://s3.amazonaws.com/babetafaperaxov/24943922105.pdf
    • https://f11c4bf2-12a6-49f8-9590-07a94b689168.filesusr.com/ugd/11276f_59765752a83944a497a5ff8ed7813537.pdf?index=true
    • https://s3.amazonaws.com/panalipolifod/miller_welding_helmet_parts.pdf
    • https://s3.amazonaws.com/dikomavomem/what_is_the_best_robot_vacuum_cleaner_to_buy.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_off000116a7.bin
3c72e778ef46fdaf1547594408e00fb657e4435b4bb0b30b9dd426d1fbc3b20e
pdf-font-stream PDF embedded font (sfnt) at offset 0x116A7 5332 bytes
font_01_sfnt_off000128f4.bin
facb6607ff22893e2c3bb1434c92b39856c144e325574a381455bc4fe6acabc3
pdf-font-stream PDF embedded font (sfnt) at offset 0x128F4 10972 bytes