Malicious PDF — malware analysis report

Static analysis result for SHA-256 81fa1b29e7af67b6…

MALICIOUS

PDF

85.0 KB Created: 2021-05-30 09:25:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-21
MD5: 2ff779f13b54080452c477aba84addf2 SHA-1: e983dce81def9d695929df5b23b8ed51bd226bab SHA-256: 81fa1b29e7af67b6c9d596a3d39135103e16bb4b334a1b2c387f86f9fa7d5c5a
186 Risk Score

Malware Insights

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

This PDF document functions as a link farm, directing users to various external sites, one of which is associated with downloading game APKs. The presence of numerous external links and the ML classifier's high confidence score indicate a malicious intent to redirect users to potentially harmful content. The ClamAV detection further confirms its malicious nature, classifying it as Pdf.Phishing.Trojan.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

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://bologen.ru/strik?utm_term=download+gta+4+for+android+full+apk+free+without+verification PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4480145/normal_5fc8b8d19a713.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4446917/normal_5fc68111064f0.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4480423/normal_6048d4df4d4ad.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4373757/normal_606e3907e0986.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4384028/normal_60137e456d097.pdfIn PDF document text
    • https://zepukuliro.weebly.com/uploads/1/3/5/9/135964459/fapasolazir.pdfIn PDF document text
    • https://dapapakutuluj.weebly.com/uploads/1/3/1/3/131384169/78453.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4415331/normal_5fd8842ec60f0.pdfIn PDF document text
    • https://bosagibanili.weebly.com/uploads/1/3/2/6/132682134/7e86fbc010fe720.pdfIn PDF document text
    • https://bumifofo.weebly.com/uploads/1/3/4/5/134598811/bonobasowap.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4454047/normal_5ff25de06a13d.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4388158/normal_6031f789e0de8.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4487423/normal_5fc94dabe5b29.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4489609/normal_60426da2b67db.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4491945/normal_603be8cfab81b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4368736/normal_6034cf218a1ce.pdfIn PDF document text
    • https://xinefozi.weebly.com/uploads/1/3/0/7/130775465/3d883148b.pdfIn PDF document text
    • https://wanukepaxe.weebly.com/uploads/1/3/4/4/134454717/799329.pdfIn PDF document text
    • https://pikimekexer.weebly.com/uploads/1/3/4/5/134587048/bbba1b.pdfIn PDF document text
    • https://toreliga.weebly.com/uploads/1/3/4/3/134335880/lufutinidorivadiw.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/8772905a-fe5e-44a6-9dc2-41728d7a2b41/7423855390.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/85d93dd0-b60e-44d7-8c36-4e64eee1bf47/50407272989.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f95446c1-e22c-4d6b-8621-c734f82d3033/how_to_adjust_the_picture_on_a_panasonic_tv.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

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000fd73.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD73 5540 bytes
SHA-256: c3e7c2fbdf80b6abb4455307794971684e101c5c5777f5dae8deebe78933e550
font_01_sfnt_off00011083.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11083 23148 bytes
SHA-256: 6ab5945173211a812ae42997e8b1f96593ba8a64856fbb7fe8b73855c484e489