HubSpot jinjava up to 2.7.5/2.8.2 Jinja Template special elements used in a template engine

Summaryinfo

A vulnerability, which was classified as critical, was found in HubSpot jinjava up to 2.7.5/2.8.2. Affected by this issue is some unknown functionality of the component Jinja Template Handler. Such manipulation leads to improper neutralization of special elements used in a template engine. This vulnerability is traded as CVE-2026-25526. The attack may be launched remotely. There is no exploit available. You should upgrade the affected component.

Detailsinfo

A vulnerability was found in HubSpot jinjava up to 2.7.5/2.8.2 and classified as critical. Affected by this issue is some unknown functionality of the component Jinja Template Handler. The manipulation with an unknown input leads to a improper neutralization of special elements used in a template engine vulnerability. Using CWE to declare the problem leads to CWE-1336. The product uses a template engine to insert or process externally-influenced input, but it does not neutralize or incorrectly neutralizes special elements or syntax that can be interpreted as template expressions or other code directives when processed by the engine. Impacted is confidentiality, integrity, and availability. CVE summarizes:

JinJava is a Java-based template engine based on django template syntax, adapted to render jinja templates. Prior to versions 2.7.6 and 2.8.3, JinJava is vulnerable to arbitrary Java execution via bypass through ForTag. This allows arbitrary Java class instantiation and file access bypassing built-in sandbox restrictions. This issue has been patched in versions 2.7.6 and 2.8.3.

The advisory is shared for download at github.com. This vulnerability is handled as CVE-2026-25526 since 02/02/2026. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. There are neither technical details nor an exploit publicly available. The MITRE ATT&CK project declares the attack technique as T1221.

Upgrading to version 2.7.6 or 2.8.3 eliminates this vulnerability. The upgrade is hosted for download at github.com. Applying the patch 3d02e504d8bbb13bf3fe019e9ca7b51dfce7a998 is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-5336). Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

• Programming Language Software

Vendor

• HubSpot

Name

• jinjava

Version

• 2.7.0
• 2.7.1
• 2.7.2
• 2.7.3
• 2.7.4
• 2.7.5
• 2.8.0
• 2.8.1
• 2.8.2

License

• open-source

Website

• Product: https://github.com/HubSpot/jinjava/

CPE 2.3info

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CPE 2.2info

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Once again VulDB remains the best source for vulnerability data.

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