CVE-2026-122131
Published:November 04, 2026
Updated:November 06, 2026
Joi 17.13.6 before 17.13.9 and 18.2.5 before 18.3.1 contains a prototype pollution vulnerability in lib/messages.js compile() and merge() that fails to reject a proto language key. Attackers supplying untrusted message configuration via any().messages(), prefs, validate options or Joi.extend can replace the compiled messages prototype, altering or breaking validation error rendering and dependent logic.
Affected Packages
https://github.com/hapijs/joi.git (GITHUB):
Affected version(s) >=v17.13.6 <v17.13.9Fix Suggestion:
Update to version v17.13.9https://github.com/hapijs/joi.git (GITHUB):
Affected version(s) >=v18.2.5 <v18.3.1Fix Suggestion:
Update to version v18.3.1Additional Notes
The description of this vulnerability differs from MITRE.
Related Resources (14)
Do you need more information?
Contact UsCVSS v4
Base Score:
6.3
Attack Vector
NETWORK
Attack Complexity
HIGH
Attack Requirements
PRESENT
Privileges Required
NONE
User Interaction
NONE
Vulnerable System Confidentiality
NONE
Vulnerable System Integrity
LOW
Vulnerable System Availability
NONE
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
3.7
Attack Vector
NETWORK
Attack Complexity
HIGH
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
LOW
Availability
NONE
Weakness Type (CWE)
Improperly Controlled Modification of Object Prototype Attributes
EPSS
Base Score:
0.33