CVE-2026-90771
Description
A flaw was found in joi. This vulnerability, known as prototype pollution, exists in the messages compilation function. A remote attacker can exploit this by supplying specially crafted __proto__ keys in custom messages. This allows the attacker to manipulate object properties, which could lead to unexpected application behavior or crashes.
Statement
A flaw in joi permits prototype manipulation when attacker-controlled JSON or configuration containing proto is supplied to the .messages() or .prefs() APIs, potentially disrupting downstream application behavior.
Mitigation
Upgrade joi to 17.13.8, 18.2.9, or later. Avoid passing untrusted data to Joi message configuration until upgraded.
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).
The following CVSS metrics and score provided are preliminary and subject to review.
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 5.9 | N/A | 3.7 |
| Attack Vector | Network | N/A | Network |
| Attack Complexity | High | N/A | High |
| Privileges Required | None | N/A | None |
| User Interaction | None | N/A | None |
| Scope | Unchanged | N/A | Unchanged |
| Confidentiality | None | N/A | None |
| Integrity Impact | High | N/A | Low |
| Availability Impact | None | N/A | None |
Vector
Red Hat: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
cve.org: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N
Understanding the Weakness (CWE)
Integrity
Technical Impact: Modify Application Data
An attacker could modify sensitive data or program variables.
Integrity
Technical Impact: Execute Unauthorized Code or Commands
Other,Integrity
Technical Impact: Varies by Context; Alter Execution Logic
Frequently Asked Questions
Not sure what something means? Check out our Security Glossary.
Want to get errata notifications? Sign up here.
