Is there a public exploit for CVE-2026-122131?

No public exploit for CVE-2026-122131 was found in Exploit-DB, Metasploit, Nuclei templates or public proof-of-concept repositories. That is an absence of evidence rather than proof that none exists.

How severe is CVE-2026-122131?

CVE-2026-122131 scores CVSS 6.3 (v4.0), rated medium.

What does CVE-2026-122131 affect?

CVE-2026-122131 affects hapijs joi.

6.3 Medium

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()…

CVE-2026-122131

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.

Assessment

CVSS: 6.3 (v4.0)
Severity: Medium
Known exploited: Not listed in CISA KEV
Exploit availability: Nothing found in Exploit-DB, Metasploit, Nuclei or public PoC repositories
Published: 4 November 2026
Last updated: 4 November 2026
Affected: hapijs · joi
Assigner: VulnCheck

CVSS vectorCVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N

At the source

EUVD (ENISA)

References

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