CVE-2026-74792

Scriban before 7.0.0 (affected versions <= 6.6.0) contains a stack overflow vulnerability in nested array initializer parsing. Deeply nested array initializers recurse through a path (ParseArrayInitializer → ParseExpression → ParseArrayInitializer) that is not covered by the ExpressionDepthLimit counter added in the fix for GHSA-wgh7-7m3c-fx25. An attacker who can supply untrusted input to Template.Parse can trigger an uncatchable StackOverflowException that immediately terminates the process, even with the default ExpressionDepthLimit enabled.

Scriban before 7.0.0 (affected versions <= 6.6.0) contains a stack overflow vulnerability in nested array initializer parsing. Deeply nested array initializers recurse through a path (ParseArrayInitializer → ParseExpression → ParseArrayInitializer) that is not covered by the ExpressionDepthLimit counter added in the fix for GHSA-wgh7-7m3c-fx25. An attacker who can supply untrusted input to Template.Parse can trigger an uncatchable StackOverflowException that immediately terminates the process, even with the default ExpressionDepthLimit enabled.

Scriban before 7.0.0 (affected versions <= 6.6.0) contains a stack overflow vulnerability in nested array initializer parsing. Deeply nested array initializers recurse through a path (ParseArrayInitializer → ParseExpression → ParseArrayInitializer) that is not covered by the ExpressionDepthLimit counter added in the fix for GHSA-wgh7-7m3c-fx25. An attacker who can supply untrusted input to Template.Parse can trigger an uncatchable StackOverflowException that immediately terminates the process, even with the default ExpressionDepthLimit enabled.

Summary

StackOverflowException via nested array initializers bypasses ExpressionDepthLimit fix (GHSA-wgh7-7m3c-fx25)

Details

The recent fix for GHSA-wgh7-7m3c-fx25 (uncontrolled recursion in parser) added ExpressionDepthLimit defaulting to 250. However, deeply nested array initializers ([[[[...) recurse through ParseArrayInitializer → ParseExpression → ParseArrayInitializer, which is a different recursion path not covered by the expression depth counter.

This causes a StackOverflowException on current main (commit b5ac4bf - "Add limits for default safety").

PoC

using Scriban;

// ExpressionDepthLimit (default 250) does NOT prevent this crash
string nested = "{{ " + new string('[', 5000) + "1" + new string(']', 5000) + " }}";
Template.Parse(nested); // StackOverflowException - process terminates

Impact

Same as GHSA-wgh7-7m3c-fx25: High severity. StackOverflowException cannot be caught with try/catch in .NET - the process terminates immediately. Any application calling Template.Parse with untrusted input is vulnerable, even with the new default ExpressionDepthLimit enabled.

Scriban before 7.0.0 (affected versions <= 6.6.0) contains a stack overflow vulnerability in nested array initializer parsing. Deeply nested array initializers recurse through a path (ParseArrayInitializer → ParseExpression → ParseArrayInitializer) that is not covered by the ExpressionDepthLimit counter added in the fix for GHSA-wgh7-7m3c-fx25. An attacker who can supply untrusted input to Template.Parse can trigger an uncatchable StackOverflowException that immediately terminates the process, even with the default ExpressionDepthLimit enabled.

Scriban before 7.0.0 (affected versions <= 6.6.0) contains a stack overflow vulnerability in nested array initializer parsing. Deeply nested array initializers recurse through a path (ParseArrayInitializer → ParseExpression → ParseArrayInitializer) that is not covered by the ExpressionDepthLimit counter added in the fix for GHSA-wgh7-7m3c-fx25. An attacker who can supply untrusted input to Template.Parse can trigger an uncatchable StackOverflowException that immediately terminates the process, even with the default ExpressionDepthLimit enabled.

Summary

StackOverflowException via nested array initializers bypasses ExpressionDepthLimit fix (GHSA-wgh7-7m3c-fx25)

Details

The recent fix for GHSA-wgh7-7m3c-fx25 (uncontrolled recursion in parser) added ExpressionDepthLimit defaulting to 250. However, deeply nested array initializers ([[[[...) recurse through ParseArrayInitializer → ParseExpression → ParseArrayInitializer, which is a different recursion path not covered by the expression depth counter.

This causes a StackOverflowException on current main (commit b5ac4bf - "Add limits for default safety").

PoC

using Scriban;

// ExpressionDepthLimit (default 250) does NOT prevent this crash
string nested = "{{ " + new string('[', 5000) + "1" + new string(']', 5000) + " }}";
Template.Parse(nested); // StackOverflowException - process terminates

Impact

Same as GHSA-wgh7-7m3c-fx25: High severity. StackOverflowException cannot be caught with try/catch in .NET - the process terminates immediately. Any application calling Template.Parse with untrusted input is vulnerable, even with the new default ExpressionDepthLimit enabled.