Malicious PDF — malware analysis report

Static analysis result for SHA-256 20a4780aee99dfbf…

MALICIOUS

PDF

82.8 KB Created: 2021-03-25 13:43:59 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-02
MD5: 9bd504916cca54bd8d2b29ec6039a9b7 SHA-1: 86b01475d21dd797260466163e0bc0b66466eab8 SHA-256: 20a4780aee99dfbf3a94ce5617266888b105e54b9a4a8dd66489c23ff1de4075
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file contains a large number of external links pointing to other PDF files hosted on disposable domains, indicative of a link farm or SEO manipulation scheme. ClamAV detected this file as 'Pdf.Phishing.Trojan', and an ML classifier also flagged it as malicious. The primary purpose appears to be directing users to potentially malicious or unwanted content through a network of linked documents.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://jacksth.ru/award?keyword=libros+de+base+de+datos+orientada+a+objetos+pdf PDF link annotation
    • https://piberarejini.weebly.com/uploads/1/3/5/3/135332679/3854991.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4383565/normal_6026c756674c4.pdfIn PDF document text
    • https://fusarutuzazeni.weebly.com/uploads/1/3/5/3/135346017/717340.pdfIn PDF document text
    • https://fujimerikav.weebly.com/uploads/1/3/4/3/134307110/modozubodube_kolodi.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4370989/normal_600a70027c371.pdfIn PDF document text
    • http://tojasojula.iblogger.org/free_full_album_zip_sites.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4368493/normal_603e40be8729f.pdfIn PDF document text
    • https://vebajixumese.weebly.com/uploads/1/3/4/4/134483039/9718897.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4501360/normal_6045bead11ec5.pdfIn PDF document text
    • https://voteriboxovoviv.weebly.com/uploads/1/3/4/3/134352377/jabetodesixusafekeli.pdfIn PDF document text
    • https://rikelakejif.weebly.com/uploads/1/3/4/8/134885243/bc8b32161e91c9.pdfIn PDF document text
    • http://bopugafuwu.scienceontheweb.net/bobosonusaruwusiponape.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4375517/normal_5fe7a0b4a8367.pdfIn PDF document text
    • http://zosuwalerikare.getenjoyment.net/74009985064.pdfIn PDF document text
    • https://wezenazuzive.weebly.com/uploads/1/3/4/7/134764498/piwajirabadem_filinuwa_wadodaxiwoz.pdfIn PDF document text
    • https://ravaruxotono.weebly.com/uploads/1/3/6/0/136087447/df6ad23fb.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4447097/normal_5fd28ad399c67.pdfIn PDF document text
    • http://vetozadep.mywebcommunity.org/rigor_in_qualitative_research_the_assessment_of_trustworthiness.pdfIn PDF document text
    • https://bujefodamefizup.weebly.com/uploads/1/3/1/0/131070612/nejevewugalopisunu.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4462732/normal_5ff7a4bebbed7.pdfIn PDF document text
    • https://gunimumatepatu.weebly.com/uploads/1/3/5/3/135313318/1193191688a.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://luzutajezilako.rf.gd/english_for_everyone_comma_rules_answers.pdfIn PDF document text
    • http://sonubadu.epizy.com/nutobetirivuzunerako.pdfIn PDF document text
    • http://mipuberepe.epizy.com/lewedobonilagu.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_off000103c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103C6 5160 bytes
SHA-256: e0145def54d73a6ad4ca5d006ae3e21d421aa735a5f83e1540c8052a204ccf0a
font_01_sfnt_off0001155f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1155F 12188 bytes
SHA-256: 07a0f78fedd1f4d27f7456906609dd5e3ce25b52efaa692223ce876e4e50725d