CVE-2026-122131 (GCVE-0-2026-122131)
Vulnerability from cvelistv5 – Published: 2026-11-04 20:36 – Updated: 2026-11-05 19:40
VLAI
EPSS
VEX
Title
Joi 17.13.6 before 17.13.9 and 18.2.5 before 18.3.1 Prototype Replacement via __proto__ Language Key
Summary
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.
Severity
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-11-05 19:39 UTC
CWE
- CWE-1321 - Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')
Assigner
VulnCheck
CNA
References
7 references
| URL | Tags |
|---|---|
| https://github.com/hapijs/joi/commit/76f5771e1afe… | patch |
| https://github.com/hapijs/joi | product |
| https://github.com/hapijs/joi/commit/dae9467cec27… | patch |
| https://github.com/hapijs/joi/pull/3164 | patchissue-tracking |
| https://github.com/hapijs/joi/security/advisories… | relatedvendor-advisory |
| https://github.com/hapijs/joi/blob/v18.3.0/lib/me… | technical-description |
| https://www.vulncheck.com/advisories/joi-17.13.6-… | third-party-advisory |
Impacted products
Date Public
2026-10-28 00:00
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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
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The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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Related by attack behaviour
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