Malicious PDF — malware analysis report

Static analysis result for SHA-256 9d433e1ef2781ef1…

MALICIOUS

PDF

76.1 KB Created: 2021-03-15 02:10:49 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 1737f5df2a5004c8f43cacdf958a9004 SHA-1: 88cb4e5942afb78cb1673572dd366b82c501b927 SHA-256: 9d433e1ef2781ef158a13582c7ef3fd3563d7746d25d5ce453ae530f186abbdb
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to PDFs, suggesting a link farm or redirection mechanism. The primary URL, https://mezovuduw.ru/award?keyword=rrb+biology+questions+pdf, indicates a lure related to biology questions. The ML classifier and ClamAV detection strongly suggest malicious intent, likely to distribute further malware or phish users. No scripts were extracted, but the PDF structure itself is used to host and link to malicious content.

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://mezovuduw.ru/award?keyword=rrb+biology+questions+pdf
    • https://cdn-cms.f-static.net/uploads/4389797/normal_603054e55244f.pdf
    • https://cdn-cms.f-static.net/uploads/4402718/normal_5fd97ff040339.pdf
    • https://cdn-cms.f-static.net/uploads/4392195/normal_5fe70666534a6.pdf
    • https://cdn-cms.f-static.net/uploads/4467945/normal_600b770f325cf.pdf
    • https://cdn-cms.f-static.net/uploads/4418171/normal_604b4b303d8cf.pdf
    • http://zanovekolasin.mywebcommunity.org/rinnai_heaters_home_depot.pdf
    • https://cdn-cms.f-static.net/uploads/4455185/normal_602b53565dd15.pdf
    • http://palupalukagu.mygamesonline.org/buwexenunexemug.pdf
    • http://nibewubixela.getenjoyment.net/che_guevara_biography_in_telugu_download.pdf
    • https://static.s123-cdn-static.com/uploads/4375907/normal_6002206b168a1.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/38a98d8d-42b4-493f-90c2-14a6acbfd6cf/91072378147.pdf
    • https://uploads.strikinglycdn.com/files/f86daf7a-0186-44e4-8ada-c501b0479878/miwugifufonoresazu.pdf
    • https://d872ce2a-2baf-4032-ab86-ab75b2f66d52.filesusr.com/ugd/338562_eb49bf351d1c4cac81e49d92a82296c9.pdf?index=true
    • http://nujilexulajuwup.atwebpages.com/hodder_cambridge_primary_english_stage_2.pdf
    • https://uploads.strikinglycdn.com/files/7f003bf0-014d-4af5-87b2-08ec47bbae42/57467644943.pdf
    • https://f1801c53-b3f5-4b94-a9b3-4bb8eb376a66.filesusr.com/ugd/af633f_00c6327705c843128c5bc2bf8c782373.pdf?index=true
    • https://21e323bd-7fdd-46e9-a6c7-4880e76d7610.filesusr.com/ugd/0a51c1_ffbb0e68e9e34c5382a9aabd3bac08ad.pdf?index=true
    • https://uploads.strikinglycdn.com/files/47986bce-2ec0-4f36-a4f4-e8a08a4c1ecf/50157250710.pdf
    • https://a3720f92-bdaa-4449-a3ff-14f36884d2d5.filesusr.com/ugd/afadc3_403097dfcedb4b57a4687a8eb9116fae.pdf?index=true
    • 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_off0000ec7d.bin
915636eb4b8af63e0df6d1fb12ad1cabe08f4a06348e23b75ff9f6f2486954b5		 pdf-font-stream PDF embedded font (sfnt) at offset 0xEC7D 5376 bytes
font_01_sfnt_off0000fed5.bin
aeb9d35c8b5e3fdfc90e00175d9b6c56a61cee77cbe2ab66dcf9a30e1ed9824f		 pdf-font-stream PDF embedded font (sfnt) at offset 0xFED5 10756 bytes

Open this report in the interactive analyzer, or submit your own file for analysis.