CVE-2026-92218
Description
A flaw was found in the release-service-utils component. This vulnerability, known as Server-Side Template Injection, allows an attacker to execute unauthorized code. By manipulating specific input fields, a malicious tenant can inject harmful commands into templates that are processed twice. This bypasses security measures, enabling the attacker to run arbitrary code within the release-service-utils system and potentially gain access to sensitive credentials.
Statement
The vulnerability in release-service-utils is rated as Important because a malicious tenant can achieve arbitrary code execution. This server-side template injection flaw arises from a two-pass rendering process where user-controlled input is re-evaluated as live Jinja template syntax, bypassing intended sandboxing. Exploitation requires the ability to influence specific text fields within release inputs, leading to compromise of the release-service-utils pod and potential access to sensitive credentials.
Mitigation
Suggestion: Remove the second-pass render, or if double expansion is required use jinja2.sandbox.ImmutableSandboxedEnvironment for both passes and reject/escape '{{', '{%', '{#' sequences in template_data values before rendering. Add a unit test asserting that a data value containing Jinja syntax is emitted literally.
Understanding the Weakness (CWE)
Access Control
Technical Impact: Bypass Protection Mechanism
In some cases, injectable code controls authentication; this may lead to a remote vulnerability.
Access Control
Technical Impact: Gain Privileges or Assume Identity
Injected code can access resources that the attacker is directly prevented from accessing.
Integrity,Confidentiality,Availability
Technical Impact: Execute Unauthorized Code or Commands
When a product allows a user's input to contain code syntax, it might be possible for an attacker to craft the code in such a way that it will alter the intended control flow of the product. As a result, code injection can often result in the execution of arbitrary code. Code injection attacks can also lead to loss of data integrity in nearly all cases, since the control-plane data injected is always incidental to data recall or writing.
Non-Repudiation
Technical Impact: Hide Activities
Often the actions performed by injected control code are unlogged.
Frequently Asked Questions
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