Packages / joi / Security

HighVulnerabilityGHSA-6h2x-m376-mqjqCVE-2026-92599Published 29 Sep 2026

joi: Quadratic regular-expression backtracking in `Joi.string().isoDate()`

Your version

Affected releases · joi

  • 18.x18.0.0 – 18.2.5Fixed in 18.2.6
  • 17.x17.2.0 – 17.13.6Fixed in 17.13.7

On 18.x, the newest line:

npm install joi@18.2.6
Every release on a timeline
18.x

  1. Affected

    18.0.0 – 18.2.5

    12 releases

  2. Fixed

    18.2.6 – 18.3.1

    6 releases, latest

17.x

  1. Not affected

    17.1.1

    1 release

  2. Affected

    17.2.0 – 17.13.6

    39 releases

  3. Fixed

    17.13.7 – 17.13.9

    3 releases

256 stable releases of joi, oldest to newest, one row per major.

What happens

Impact

Any application that validates a user-supplied string with Joi.string().isoDate() can be stalled by a single request. One of the regular expressions the rule runs over the input was unanchored, so a valid ISO date followed by a long run of fractional-second digits made the regex engine restart its search from every position in the string, costing time proportional to the square of the input length. 64 KB of digits costs about 1.4 s and 256 KB about 22 s.

Patches

Upgrade to version 17.13.7 or 18.2.6 depending on your current major version.

Workarounds

None except capping the length of the string before it reaches joi.