CVE-2026-4926

HIGH

7.5

Description

Impact: A bad regular expression is generated any time you have multiple sequential optional groups (curly brace syntax), such as `{a}{b}{c}:z`. The generated regex grows exponentially with the number of groups, causing denial of service. Patches: Fixed in version 8.4.0. Workarounds: Limit the number of sequential optional groups in route patterns. Avoid passing user-controlled input as route patterns.

CVE Details

CVSS v3.1 Score7.5

SeverityHIGH

CVSS VectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Attack VectorNETWORK

ComplexityLOW

Privileges RequiredNONE

User InteractionNONE

Published3/26/2026

Last Modified3/30/2026

Sourcenvd

Honeypot Sightings0

Weaknesses (CWE)

CWE-400CWE-1333

References

https://cna.openjsf.org/security-advisories.html(ce714d77-add3-4f53-aff5-83d477b104bb)

IOC Correlations

No correlations recorded

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