{"id":"CVE-2026-74790","aliases":["EUVD-2026-59956","GHSA-5wr9-m6jw-xx44","GHSA-6w6f-93jg-2qf5"],"status":"published","title":"Scriban before 7.0.0 MemberFilter Bypass via TemplateContext Cache","description":"Scriban before 7.0.0 caches TypedObjectAccessor by Type only without considering MemberFilter changes, allowing reused TemplateContext instances to expose members that should be hidden. Attackers can access filtered properties and fields by reusing a TemplateContext after tightening its MemberFilter, bypassing sandbox policies across requests or tenants.","severity":{"version":"4.0","score":9.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N","level":"critical","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-10","score":0.00471,"percentile":0.4104,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-693"],"published":"2026-03-24T22:11:38Z","modified":"2026-10-28T02:30:39Z","fixes":[{"ecosystem":"NuGet","package":"scriban","fixed_in":["7.0.0"],"sources":["ghsa","osv"]},{"ecosystem":"NuGet","package":"Scriban.Signed","fixed_in":["7.0.0"],"sources":["ghsa","osv"]}],"affected":[{"source":"ghsa","ecosystem":"NuGet","package":"scriban","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"7.0.0"}]}]},{"source":"ghsa","ecosystem":"NuGet","package":"Scriban.Signed","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"7.0.0"}]}]},{"source":"osv","ecosystem":"NuGet","package":"scriban","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"7.0.0"}]}],"versions":["0.1.0","0.10.0","0.11.0","0.12.0","0.12.1","0.13.0","0.14.0","0.15.0","0.16.0","0.2.0","0.2.1","0.2.2","0.3.0","0.3.1","0.3.1-pre028","0.4.0","0.5.0","0.6.0","0.7.0","0.9.0","0.9.0-pre100","0.9.1","1.0.0","1.0.0-beta-001","1.0.0-beta-002","1.0.0-beta-003","1.0.0-beta-004","1.0.0-beta-005","1.0.0-beta-006","1.1.0","1.1.1","1.2.0","1.2.1","1.2.2","1.2.3","1.2.4","1.2.5","1.2.6","1.2.7","1.2.8","1.2.9","2.0.0","2.0.0-alpha-001","2.0.0-alpha-002","2.0.0-alpha-003","2.0.0-alpha-004","2.0.0-alpha-005","2.0.0-alpha-006","2.0.1","2.1.0","2.1.1","2.1.2","2.1.3","2.1.4","3.0.0","3.0.1","3.0.2","3.0.3","3.0.4","3.0.5","3.0.6","3.0.7","3.1.0","3.2.0","3.2.1","3.2.2","3.3.0","3.3.1","3.3.2","3.3.3","3.4.0","3.4.1","3.4.2","3.5.0","3.6.0","3.7.0","3.8.0","3.8.1","3.8.2","3.9.0","4.0.0","4.0.1","4.0.2","4.1.0","5.0.0","5.1.0","5.10.0","5.11.0","5.12.0","5.12.1","5.2.0","5.3.0","5.4.0","5.4.1","5.4.2","5.4.3","5.4.4","5.4.5","5.4.6","5.5.0","5.5.1","5.5.2","5.6.0","5.7.0","5.8.0","5.9.0","5.9.1","6.0.0","6.1.0","6.2.0","6.2.1","6.3.0","6.4.0","6.5.0","6.5.1","6.5.2","6.5.3","6.5.4","6.5.5","6.5.6","6.5.7","6.5.8","6.6.0"]},{"source":"osv","ecosystem":"NuGet","package":"Scriban.Signed","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"7.0.0"}]}],"versions":["0.10.0","0.11.0","0.12.0","0.12.1","0.13.0","0.14.0","0.15.0","0.16.0","0.9.0","0.9.1","1.0.0","1.0.0-beta-001","1.0.0-beta-002","1.0.0-beta-003","1.0.0-beta-004","1.0.0-beta-005","1.0.0-beta-006","1.1.0","1.1.1","1.2.0","1.2.1","1.2.2","1.2.3","1.2.4","1.2.5","1.2.6","1.2.7","1.2.8","1.2.9","2.0.0","2.0.0-alpha-001","2.0.0-alpha-002","2.0.0-alpha-003","2.0.0-alpha-004","2.0.0-alpha-005","2.0.0-alpha-006","2.0.1","2.1.0","2.1.1","2.1.2","2.1.3","2.1.4","3.0.0","3.0.1","3.0.2","3.0.3","3.0.4","3.0.5","3.0.6","3.0.7","3.1.0","3.2.0","3.2.1","3.2.2","3.3.0","3.3.1","3.3.2","3.3.3","3.4.0","3.4.1","3.4.2","3.5.0","3.6.0","3.7.0","3.8.0","3.8.1","3.8.2","3.9.0","4.0.0","4.0.1","4.0.2","4.1.0","5.0.0","5.1.0","5.10.0","5.11.0","5.12.0","5.12.1","5.2.0","5.3.0","5.4.0","5.4.1","5.4.2","5.4.3","5.4.4","5.4.5","5.4.6","5.5.0","5.5.1","5.5.2","5.6.0","5.7.0","5.8.0","5.9.0","5.9.1","6.0.0","6.1.0","6.2.0","6.2.1","6.3.0","6.4.0","6.5.0","6.5.1","6.5.2","6.5.3","6.5.4","6.5.5","6.5.6","6.5.7","6.5.8","6.6.0"]}],"products":[{"vendor":"scriban","product":"scriban"}],"references":[{"url":"https://github.com/scriban/scriban/security/advisories/GHSA-5wr9-m6jw-xx44","tags":["vendor-advisory","exploit","advisory","web"]},{"url":"https://www.vulncheck.com/advisories/scriban-before-memberfilter-bypass-via-templatecontext-cache","tags":["third-party-advisory","advisory"]},{"url":"https://github.com/advisories/GHSA-5wr9-m6jw-xx44"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-74790","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-6w6f-93jg-2qf5"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/74xxx/CVE-2026-74790.json","tags":["advisory"]},{"url":"https://github.com/scriban/scriban","tags":["package"]}],"sources":{"cve":[{"id":"CVE-2026-74790","title":"Scriban before 7.0.0 MemberFilter Bypass via TemplateContext Cache","description":"Scriban before 7.0.0 caches TypedObjectAccessor by Type only without considering MemberFilter changes, allowing reused TemplateContext instances to expose members that should be hidden. Attackers can access filtered properties and fields by reusing a TemplateContext after tightening its MemberFilter, bypassing sandbox policies across requests or tenants.","status":"published","published":"2026-08-16T13:14:14.417Z","modified":"2026-08-17T15:31:51.759Z","cvss":[{"version":"4.0","score":9.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N","level":"critical","assessor":"cna"},{"version":"3.1","score":9.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N","level":"critical","assessor":"cna"}],"cwes":["CWE-693"],"updated_at":"2026-11-02T14:20:03.081354Z"}],"euvd":[{"id":"EUVD-2026-59956","description":"Scriban before 7.0.0 caches TypedObjectAccessor by Type only without considering MemberFilter changes, allowing reused TemplateContext instances to expose members that should be hidden. Attackers can access filtered properties and fields by reusing a TemplateContext after tightening its MemberFilter, bypassing sandbox policies across requests or tenants.","status":"published","published":"2026-08-16T13:14:14Z","modified":"2026-08-17T15:31:51Z","cvss":[{"version":"4.0","score":9.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N","level":"critical"}],"updated_at":"2026-11-02T18:01:49.335011Z"}],"ghsa":[{"id":"GHSA-5wr9-m6jw-xx44","title":"Scriban: Sandbox escape due to TypedObjectAccessorcache bypassing MemberFilter after TemplateContext reuse","description":"## Summary\n\n`TemplateContext` caches type accessors by `Type` only, but those accessors are built using the current `MemberFilter` and `MemberRenamer`. When a `TemplateContext` is reused and the filter is tightened for a later render, Scriban still reuses the old accessor and continues exposing members that should now be hidden.\n\n## Details\n\nThe relevant code path is:\n\n- `TemplateContext.GetMemberAccessor()` caches accessors in `_memberAccessors` by `Type` in `src/Scriban/TemplateContext.cs` lines 850–863.\n- For plain .NET objects, `GetMemberAccessorImpl()` creates a new `TypedObjectAccessor(type, _keyComparer, MemberFilter, MemberRenamer)` in `src/Scriban/TemplateContext.cs` lines 909–939.\n- `TypedObjectAccessor` stores the current filter and precomputes the exposed member set in its constructor and `PrepareMembers()` in `src/Scriban/Runtime/Accessors/TypedObjectAccessor.cs` lines 33–40 and 119–179.\n- Member access later goes through `ScriptMemberExpression.GetValue()` in `src/Scriban/Syntax/Expressions/ScriptMemberExpression.cs` lines 67–95, which uses the cached accessor.\n- `TemplateContext.Reset()` does **not** clear `_memberAccessors` in `src/Scriban/TemplateContext.cs` lines 877–902.\n\nAs a result, once a permissive accessor has been created for a given type, changing `TemplateContext.MemberFilter` later does not take effect for that type on the same reused context.\n\nThis is especially relevant because the Scriban docs explicitly recommend `TemplateContext.MemberFilter` for indirect .NET object exposure.\n\n---\n\n## Proof of Concept\n\n### Setup\n\n```bash\nmkdir scriban-poc2\ncd scriban-poc2\ndotnet new console --framework net8.0\ndotnet add package Scriban --version 6.6.0\n```\n\n### `Program.cs`\n\n```csharp\nusing System.Reflection;\nusing Scriban;\nusing Scriban.Runtime;\n\nvar template = Template.Parse(\"{{ model.secret }}\");\n\nvar context = new TemplateContext\n{\n    EnableRelaxedMemberAccess = false\n};\n\nvar globals = new ScriptObject();\nglobals[\"model\"] = new SensitiveModel();\ncontext.PushGlobal(globals);\n\ncontext.MemberFilter = _ =\u003e true;\nConsole.WriteLine(\"first=\" + template.Render(context));\n\ncontext.Reset();\n\nvar globals2 = new ScriptObject();\nglobals2[\"model\"] = new SensitiveModel();\ncontext.PushGlobal(globals2);\n\ncontext.MemberFilter = member =\u003e member.Name == nameof(SensitiveModel.Public);\n\nConsole.WriteLine(\"second=\" + template.Render(context));\n\nsealed class SensitiveModel\n{\n    public string Public =\u003e \"ok\";\n    public string Secret =\u003e \"leaked\";\n}\n```\n\n### Run\n\n```bash\ndotnet run\n```\n\n### Actual Output\n\n```\nfirst=leaked\nsecond=leaked\n```\n\n### Expected Behavior\n\nThe second render should fail or stop exposing `Secret`, because the filter only allows `Public` and `EnableRelaxedMemberAccess` is disabled.\n\nThis reproduces a direct filter bypass caused by the stale cached accessor.\n\n---\n\n## Impact\n\nThis is a protection-mechanism bypass. Applications that use `TemplateContext.MemberFilter` as part of their sandbox or object-exposure policy can unintentionally expose hidden members across requests when they reuse a `TemplateContext`.\n\nThe impact includes:\n\n- Unauthorized read access to filtered properties or fields\n- Unauthorized writes if the filtered member also has a setter\n- Policy bypass across requests, users, or tenants when contexts are pooled","status":"published","published":"2026-03-24T22:11:38Z","modified":"2026-07-06T13:08:11Z","cvss":[{"version":"3.1","score":9.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N","level":"critical"}],"cwes":["CWE-693"],"updated_at":"2026-11-02T14:40:38.48196Z"},{"id":"GHSA-6w6f-93jg-2qf5","title":"Scriban before 7.0.0 caches TypedObjectAccessor by Type only without considering MemberFilter...","description":"Scriban before 7.0.0 caches TypedObjectAccessor by Type only without considering MemberFilter changes, allowing reused TemplateContext instances to expose members that should be hidden. Attackers can access filtered properties and fields by reusing a TemplateContext after tightening its MemberFilter, bypassing sandbox policies across requests or tenants.","status":"published","published":"2026-08-16T15:30:27Z","modified":"2026-08-16T15:30:27Z","cvss":[{"version":"4.0","score":9.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"critical"},{"version":"3.1","score":9.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N","level":"critical"}],"cwes":["CWE-693"],"updated_at":"2026-11-02T15:10:32.287939Z"}],"nvd":[{"id":"CVE-2026-74790","description":"Scriban before 7.0.0 caches TypedObjectAccessor by Type only without considering MemberFilter changes, allowing reused TemplateContext instances to expose members that should be hidden. Attackers can access filtered properties and fields by reusing a TemplateContext after tightening its MemberFilter, bypassing sandbox policies across requests or tenants.","status":"published","published":"2026-08-16T14:16:57.05Z","modified":"2026-08-31T20:30:14.457Z","cvss":[{"version":"4.0","score":9.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"critical","assessor":"secondary"},{"version":"3.1","score":9.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N","level":"critical","assessor":"secondary"}],"cwes":["CWE-693"],"updated_at":"2026-11-02T14:12:38.647684Z"}],"osv":[{"id":"CVE-2026-74790","title":"Scriban before 7.0.0 MemberFilter Bypass via TemplateContext Cache","description":"Scriban before 7.0.0 caches TypedObjectAccessor by Type only without considering MemberFilter changes, allowing reused TemplateContext instances to expose members that should be hidden. Attackers can access filtered properties and fields by reusing a TemplateContext after tightening its MemberFilter, bypassing sandbox policies across requests or tenants.","status":"published","published":"2026-08-16T13:14:14.417Z","modified":"2026-10-28T02:30:39.907391652Z","cvss":[{"version":"4.0","score":9.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N","level":"critical"}],"cwes":["CWE-693"],"updated_at":"2026-11-02T15:45:16.748692Z"},{"id":"GHSA-5wr9-m6jw-xx44","title":"Scriban: Sandbox escape due to TypedObjectAccessorcache bypassing MemberFilter after TemplateContext reuse","description":"## Summary\n\n`TemplateContext` caches type accessors by `Type` only, but those accessors are built using the current `MemberFilter` and `MemberRenamer`. When a `TemplateContext` is reused and the filter is tightened for a later render, Scriban still reuses the old accessor and continues exposing members that should now be hidden.\n\n## Details\n\nThe relevant code path is:\n\n- `TemplateContext.GetMemberAccessor()` caches accessors in `_memberAccessors` by `Type` in `src/Scriban/TemplateContext.cs` lines 850–863.\n- For plain .NET objects, `GetMemberAccessorImpl()` creates a new `TypedObjectAccessor(type, _keyComparer, MemberFilter, MemberRenamer)` in `src/Scriban/TemplateContext.cs` lines 909–939.\n- `TypedObjectAccessor` stores the current filter and precomputes the exposed member set in its constructor and `PrepareMembers()` in `src/Scriban/Runtime/Accessors/TypedObjectAccessor.cs` lines 33–40 and 119–179.\n- Member access later goes through `ScriptMemberExpression.GetValue()` in `src/Scriban/Syntax/Expressions/ScriptMemberExpression.cs` lines 67–95, which uses the cached accessor.\n- `TemplateContext.Reset()` does **not** clear `_memberAccessors` in `src/Scriban/TemplateContext.cs` lines 877–902.\n\nAs a result, once a permissive accessor has been created for a given type, changing `TemplateContext.MemberFilter` later does not take effect for that type on the same reused context.\n\nThis is especially relevant because the Scriban docs explicitly recommend `TemplateContext.MemberFilter` for indirect .NET object exposure.\n\n---\n\n## Proof of Concept\n\n### Setup\n\n```bash\nmkdir scriban-poc2\ncd scriban-poc2\ndotnet new console --framework net8.0\ndotnet add package Scriban --version 6.6.0\n```\n\n### `Program.cs`\n\n```csharp\nusing System.Reflection;\nusing Scriban;\nusing Scriban.Runtime;\n\nvar template = Template.Parse(\"{{ model.secret }}\");\n\nvar context = new TemplateContext\n{\n    EnableRelaxedMemberAccess = false\n};\n\nvar globals = new ScriptObject();\nglobals[\"model\"] = new SensitiveModel();\ncontext.PushGlobal(globals);\n\ncontext.MemberFilter = _ =\u003e true;\nConsole.WriteLine(\"first=\" + template.Render(context));\n\ncontext.Reset();\n\nvar globals2 = new ScriptObject();\nglobals2[\"model\"] = new SensitiveModel();\ncontext.PushGlobal(globals2);\n\ncontext.MemberFilter = member =\u003e member.Name == nameof(SensitiveModel.Public);\n\nConsole.WriteLine(\"second=\" + template.Render(context));\n\nsealed class SensitiveModel\n{\n    public string Public =\u003e \"ok\";\n    public string Secret =\u003e \"leaked\";\n}\n```\n\n### Run\n\n```bash\ndotnet run\n```\n\n### Actual Output\n\n```\nfirst=leaked\nsecond=leaked\n```\n\n### Expected Behavior\n\nThe second render should fail or stop exposing `Secret`, because the filter only allows `Public` and `EnableRelaxedMemberAccess` is disabled.\n\nThis reproduces a direct filter bypass caused by the stale cached accessor.\n\n---\n\n## Impact\n\nThis is a protection-mechanism bypass. Applications that use `TemplateContext.MemberFilter` as part of their sandbox or object-exposure policy can unintentionally expose hidden members across requests when they reuse a `TemplateContext`.\n\nThe impact includes:\n\n- Unauthorized read access to filtered properties or fields\n- Unauthorized writes if the filtered member also has a setter\n- Policy bypass across requests, users, or tenants when contexts are pooled","status":"published","published":"2026-03-24T22:11:38Z","modified":"2026-08-17T03:55:59.336921959Z","cvss":[{"version":"3.1","score":9.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N","level":"critical"}],"cwes":["CWE-693"],"updated_at":"2026-11-02T15:46:38.911014Z"}]}}