CVE-2025-68156
Description
A flaw was found in Expr, an expression language and expression evaluation for Go. This vulnerability allows a denial of service (DoS) via recursive traversal over user-provided deeply nested or cyclic data structures without enforcing a maximum recursion depth, leading to a stack overflow panic and application crash.
Statement
This vulnerability is rated Important for Red Hat products utilizing the Expr Go library because it can lead to a denial-of-service. Exploitation requires an application to evaluate expressions against untrusted or insufficiently validated data structures containing deeply nested or cyclic references, which can cause a stack overflow and application crash. Products that do not process untrusted input with Expr are not affected.
Mitigation
To mitigate this issue, applications using the `Expr` library should ensure that evaluation environments do not contain cyclic references. Additionally, externally supplied data structures must be validated or sanitized before being passed to `Expr` for evaluation. As a last-resort defensive measure, expression evaluation can be wrapped with panic recovery to prevent a full process crash.
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 Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 7.5 | N/A | 7.5 |
| Attack Vector | Network | N/A | Network |
| Attack Complexity | Low | N/A | Low |
| Privileges Required | None | N/A | None |
| User Interaction | None | N/A | None |
| Scope | Unchanged | N/A | Unchanged |
| Confidentiality | None | N/A | None |
| Integrity Impact | None | N/A | None |
| Availability Impact | High | N/A | High |
Vector
Red Hat: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
cve.org: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Understanding the Weakness (CWE)
Availability
Technical Impact: DoS: Resource Consumption (CPU); DoS: Resource Consumption (Memory); DoS: Resource Consumption (Other)
When allocating resources without limits, an attacker could prevent other systems, applications, or processes from accessing the same type of resource. It can be easy for an attacker to consume many resources by rapidly making many requests or causing larger resources to be used than is needed.
Frequently Asked Questions
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