{"id":13840961,"url":"https://github.com/mobdk/Upsilon","last_synced_at":"2025-07-11T09:34:14.477Z","repository":{"id":42771674,"uuid":"400179934","full_name":"mobdk/Upsilon","owner":"mobdk","description":"Upsilon execute shellcode with syscalls - no API like NtProtectVirtualMemory is used","archived":false,"fork":false,"pushed_at":"2021-08-26T16:09:08.000Z","size":1079,"stargazers_count":92,"open_issues_count":0,"forks_count":20,"subscribers_count":2,"default_branch":"main","last_synced_at":"2024-08-05T17:26:18.745Z","etag":null,"topics":[],"latest_commit_sha":null,"homepage":null,"language":"C#","has_issues":true,"has_wiki":null,"has_pages":null,"mirror_url":null,"source_name":null,"license":null,"status":null,"scm":"git","pull_requests_enabled":true,"icon_url":"https://github.com/mobdk.png","metadata":{"files":{"readme":"README.md","changelog":null,"contributing":null,"funding":null,"license":null,"code_of_conduct":null,"threat_model":null,"audit":null,"citation":null,"codeowners":null,"security":null,"support":null}},"created_at":"2021-08-26T13:31:52.000Z","updated_at":"2024-07-29T03:20:21.000Z","dependencies_parsed_at":"2022-08-29T13:51:25.566Z","dependency_job_id":null,"html_url":"https://github.com/mobdk/Upsilon","commit_stats":null,"previous_names":[],"tags_count":0,"template":false,"template_full_name":null,"repository_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/mobdk%2FUpsilon","tags_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/mobdk%2FUpsilon/tags","releases_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/mobdk%2FUpsilon/releases","manifests_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/mobdk%2FUpsilon/manifests","owner_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/owners/mobdk","download_url":"https://codeload.github.com/mobdk/Upsilon/tar.gz/refs/heads/main","host":{"name":"GitHub","url":"https://github.com","kind":"github","repositories_count":225712913,"owners_count":17512516,"icon_url":"https://github.com/github.png","version":null,"created_at":"2022-05-30T11:31:42.601Z","updated_at":"2022-07-04T15:15:14.044Z","host_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub","repositories_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories","repository_names_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repository_names","owners_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/owners"}},"keywords":[],"created_at":"2024-08-04T17:01:00.348Z","updated_at":"2024-11-21T10:31:05.107Z","avatar_url":"https://github.com/mobdk.png","language":"C#","readme":"# Upsilon\nUpsilon execute shellcode with syscalls - no API like NtProtectVirtualMemory is used\n\nNtProtectVirtualMemory is used in many PoC to change allocated memory with RWX, this PoC do not use any API calls but create a MemoryMappedFile\nto execute our shellcode with syscalls.\n\nResolver function is just a \"sinkhole\" for the Mimikatz payload, Mimikatz is converted to shellcode and then converted to 3 digits numeric format, \nthe final code is pasted in the compiled Upsilon.exe with a hex editor, this technique breaks the string logic in C# string and makes it hard for\nAV/EDR to analyse the contex both before execution and at execution.\n\nWindows version is obtained from shared KUSER_SHARED_DATA structure:\n```\nIntPtr KUSER_SHARED_DATA = new IntPtr(0x7FFE0000);\nIntPtr ptrMajorVersion = (IntPtr)(KUSER_SHARED_DATA + 0x026C);\ninfo.dwMajorVersion = *(int*)(ptrMajorVersion);\nIntPtr ptrMinorVersion = (IntPtr)(KUSER_SHARED_DATA + 0x0270);\ninfo.dwMinorVersion = *(int*)(ptrMinorVersion);\nIntPtr ptrBuildNumber = (IntPtr)(KUSER_SHARED_DATA + 0x0260);\ninfo.dwBuildNumber = *(int*)(ptrBuildNumber);\n```\nTwo syscalls is used: NtCreateSection/0x004A and NtMapViewOfSection/0x0028\n\nThis is tested on Windows 10 build 20H2 64 bit only.\n\nCompile: csc.exe /platform:x64 /target:exe /unsafe Upsilon.cs\n\nUpsilon.exe is compiled version with Mimikatz embedded and ready to test\n","funding_links":[],"categories":["C# #"],"sub_categories":[],"project_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Fmobdk%2FUpsilon","html_url":"https://awesome.ecosyste.ms/projects/github.com%2Fmobdk%2FUpsilon","lists_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Fmobdk%2FUpsilon/lists"}