CVE-2026-90771
Description
joi before versions 17.13.8 and 18.2.9 contains a prototype pollution vulnerability in the messages compilation function that accepts __proto__ as an error code. Attackers can supply __proto__ keys in custom messages to replace the returned object's prototype, breaking downstream code relying on Object.prototype methods.
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
No mitigations published for this CVE yet.
The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.
Propose a mitigation on Community Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here withsource_tier=community-verified.
References
- https://github.com/hapijs/joi
- https://github.com/hapijs/joi/blob/v18.2.8/lib/messages.js
- https://github.com/hapijs/joi/commit/5b8333c9177e08b4ef4ed02903c2d657084e7afb
- https://github.com/hapijs/joi/issues/3150
- https://www.vulncheck.com/advisories/joi-before-17.13.8-and-18.2.9-prototype-pollution-via-messages
CWEs
CWE-1321
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.