Scriban before 7.5.3 contains a resource exhaustion vulnerability that allows untrusted template authors to exhaust memory and CPU because builtins like math.format, regex.replace and string.escape skip the LimitToString allocation guard. Attackers can submit small templates using huge format precision specifiers, shared-structure array comparison, BigInteger multiplication or exponential function recursion that ignore LoopLimit and CancellationToken, crashing or stalling multi-tenant hosts.

Scriban before 7.5.2 contains an information disclosure and object manipulation vulnerability that allows template authors to access .NET internals of function values through reflection member accessors. Attackers can use array.map to read Target, Method, or ReturnType on imported delegates, exposing and overwriting service properties, captured closure secrets, and assembly paths.

Scriban before 7.5.3 contains a resource exhaustion vulnerability that allows untrusted template authors to exhaust memory and CPU because builtins like math.format, regex.replace and string.escape skip the LimitToString allocation guard. Attackers can submit small templates using huge format precision specifiers, shared-structure array comparison, BigInteger multiplication or exponential function recursion that ignore LoopLimit and CancellationToken, crashing or stalling multi-tenant hosts.

Scriban before 7.5.2 contains an information disclosure and object manipulation vulnerability that allows template authors to access .NET internals of function values through reflection member accessors. Attackers can use array.map to read Target, Method, or ReturnType on imported delegates, exposing and overwriting service properties, captured closure secrets, and assembly paths.

Scriban versions 6.6.0 through 7.2.0 contain a non-enforcing ExpressionDepthLimit guard that fails to stop recursive descent parsing of deeply nested expressions. Attackers can supply templates with deeply nested parentheses, array initializers, object initializers, or unary operators to trigger an uncatchable StackOverflowException that immediately terminates the host process.

Scriban before 7.0.0 contains an uncontrolled recursion vulnerability in the object.tojson builtin function that lacks depth limits and circular reference detection. Attackers can craft templates with self-referencing objects to trigger unbounded recursion, causing a StackOverflowException that fatally terminates the hosting .NET process.

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 contains three distinct denial-of-service vulnerabilities in expression evaluation that bypass existing safety controls through unbounded string multiplication, uncontrolled BigInteger shift operations, and LoopLimit bypass via range enumeration in builtin functions. Attackers who can supply templates can cause out-of-memory exceptions or CPU exhaustion, typically terminating the entire host process.

Scriban before 7.0.0 fails to clear the CachedTemplates dictionary when TemplateContext.Reset() is called, allowing cached templates to persist across reused contexts. Attackers can exploit request-dependent ITemplateLoader implementations to access previously authorized template content from earlier renders without triggering TemplateLoader.Load() again.

Scriban before 7.0.0 (affected versions <= 6.6.0) contains a denial-of-service vulnerability in which the LimitToString safety limit (default 1MB) can be bypassed because ObjectToString resets the per-call length counter (currentToStringLength) on every top-level call and StringBuilderOutput enforces no cumulative output-size limit. An attacker who can supply a template can render a near-limit string repeatedly in a loop, allocating approximately 1GB of memory and causing an out-of-memory condition that crashes the host application.

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.

Scriban before 7.0.0 (affected <= 6.6.0) applies its LoopLimit constraint only to script loop statements and not to expensive iteration performed inside built-in operators and functions. As a result, a single expression such as {{ 1..1000000 | array.size }} — or a memory-amplification expression such as {{ 'A' 200000000 }} — can force large CPU or memory consumption even when LoopLimit is configured to a very small value, resulting in denial of service. Applications that render attacker-controlled templates and rely on LoopLimit for safe execution are affected.

Scriban before 6.6.0 contains an infinite recursion vulnerability in object rendering when the ObjectRecursionLimit property defaults to unlimited. Attackers can supply circular reference objects to the template context, exhausting stack space and triggering an uncatchable StackOverflowException that terminates the hosting process.

Scriban before 6.6.0 contains an uncontrolled recursion vulnerability in its recursive-descent parser. The parser does not enforce a default expression depth limit (the ExpressionDepthLimit property in ParserOptions defaults to null/disabled), so an attacker who controls template input can supply a deeply nested template (e.g., thousands of nested parentheses or blocks) that exhausts thread stack space and raises a StackOverflowException. Because a StackOverflowException cannot be caught in .NET, this causes immediate, unrecoverable termination of the hosting process, resulting in a denial of service. Applications that process untrusted or user-supplied templates can be exploited remotely without authentication.