Scriban up to 6.x Built-in Operators denial of service

Summaryinfo

A vulnerability identified as problematic has been detected in Scriban up to 6.x. This impacts an unknown function of the component Built-in Operators. The manipulation leads to denial of service. This vulnerability is traded as CVE-2026-74789. It is possible to initiate the attack remotely. There is no exploit available.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in Scriban up to 6.x. This issue affects some unknown functionality of the component Built-in Operators. The manipulation with an unknown input leads to a denial of service vulnerability. Using CWE to declare the problem leads to CWE-404. The product does not release or incorrectly releases a resource before it is made available for re-use. Impacted is availability. The summary by CVE is:

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.

The advisory is shared at github.com. The identification of this vulnerability is CVE-2026-74789 since 08/16/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Neither technical details nor an exploit are publicly available. MITRE ATT&CK project uses the attack technique T1499 for this issue.

Upgrading to version 7.0.0 eliminates this vulnerability.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Name

• Scriban

Version

• 6.x

Website

• Product: https://github.com/scriban/scriban/

CPE 2.3info

• 🔒

CPE 2.2info

• 🔒

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Discussion