Vulnerability in Scriban (CVE-2026-74791)
Summary
Vulnerability in Scriban (CVE-2026-74791). Confidential information can be exposed externally.
Original description
The description as published by the source.
Summary
TemplateContext.Reset() claims that a TemplateContext can be reused safely on the same thread, but it does not clear CachedTemplates. If an application pools TemplateContext objects and uses an ITemplateLoader that resolves content per request, tenant, or user, a previously authorized include can be served to later renders without calling TemplateLoader.Load() again.
Details
The relevant code path is:
TemplateContext.Reset()only clears output, globals, cultures, and source files insrc/Scriban/TemplateContext.cslines 877–902.CachedTemplatesis initialized once and kept on the context insrc/Scriban/TemplateContext.csline 197.includeresolves templates throughIncludeFunction.Invoke()insrc/Scriban/Functions/IncludeFunction.cslines 29–43.IncludeFunction.Invoke()callsTemplateContext.GetOrCreateTemplate()insrc/Scriban/TemplateContext.cslines 1249–1256.- If a template path is already present in
CachedTemplates, Scriban returns the cached compiled template and does not callTemplateLoader.Load()again.
This becomes a security issue when ITemplateLoader.Load() returns request-dependent content. A first render can prime the cache with an admin-only or tenant-specific template, and later renders on the same reused TemplateContext will receive that stale template even after Reset().
Proof of Concept
Setup
mkdir scriban-poc1
cd scriban-poc1
dotnet new console --framework net8.0…
Source: NIST National Vulnerability Database NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-74791 has been found in Scriban.
Confidential information can be exposed externally. CVSS score: 8.6/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Scriban CVE-2026-74791" on the vendor's site.
CVE-2026-74791 (Scriban) — CWE-226 / CVSS v3 8.6
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (CWE-226) exists in Scriban.
Check the vendor advisory for the affected versions of Scriban.
Severity: High (CVSS 8.6/10). Confidential information can be exposed externally.
Update to the patched release per vendor advisory.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'Scriban' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
grep -r 'Scriban' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
Scribanを grep し、稼働しているサービス・バージョンを把握する。 -
2Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Affected packages
References
- package github.com
- web github.com
- web disclosure@vulncheck.com
- web nvd.nist.gov
- web github.com