CVE-2024-56326

Description

A flaw was found in the Jinja package. In affected versions of Jinja, an oversight in how the Jinja sandboxed environment detects calls to str.format allows an attacker that controls the content of a template to execute arbitrary Python code. To exploit the vulnerability, an attacker needs to control the content of a template. Whether that is the case depends on the type of application using Jinja. This vulnerability impacts users of applications that execute untrusted templates. Jinja's sandbox does catch calls to str.format and ensures they don't escape the sandbox. However, storing a reference to a malicious string's format method is possible, then passing that to a filter that calls it. No such filters are built into Jinja but could be present through custom filters in an application. After the fix, such indirect calls are also handled by the sandbox.

Statement

This vulnerability is rated as Moderate due to an oversight in Jinja's sandbox environment, allowing attackers to execute arbitrary Python code through controlled template content. This requires control over template content, making exploitation possible only in specific applications, thus limiting its overall impact.

Common Vulnerability Scoring System (CVSS) Score Details

Info alert:Important note

CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).

CVSS v3 Score Breakdown

Red HatNVDcve.org
Base Score6.3N/A7.8
Attack VectorLocalN/ALocal
Attack ComplexityHighN/ALow
Privileges RequiredHighN/ALow
User InteractionRequiredN/ANone
ScopeUnchangedN/AUnchanged
ConfidentialityHighN/AHigh
Integrity ImpactHighN/AHigh
Availability ImpactHighN/AHigh

Vector

Red Hat: CVSS:3.1/AV:L/AC:H/PR:H/UI:R/S:U/C:H/I:H/A:H

cve.org: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

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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