A vulnerability was found in all versions of Keycloak Gatekeeper, where on using lower case HTTP headers (via cURL) an attacker can bypass our Gatekeeper. Lower case headers are also accepted by some webservers (e.g. Jetty). This means there is no protection when we put a Gatekeeper in front of a Jetty server and use lowercase headers.
CVSS v4.0 Metrics
Exploitability
Attack VectorNetwork
ComplexityLow
RequirementsPresent
PrivilegesNone
User InteractionNone
Threat
Exploit MaturityUnreported
Vulnerable System
ConfidentialityLow
IntegrityLow
AvailabilityLow
Subsequent System
ConfidentialityNone
IntegrityNone
AvailabilityNone
Supplemental
SafetyNegligible
AutomatableYes
RecoveryAutomatic
Value DensityConcentrated
UrgencyMedium
Change Log
| Date | Source | Changes | Score |
|---|
| 2026-07-21 | nvd | AV: P→N, AC: H→L, PR: H→N, UI: A→N, VC: N→L, VI: N→L, VA: N→L | 0.0 → 1.7 |
| 2026-07-21 | cve.org | initial, patch: Unavailable | 0.0 |
Affected Software
| Vendor | Product | Version |
|---|
| n/a | keycloak | all versions as of 2021-02-22 |
| redhat | louketo_proxy | All versions |
Published: 2021-02-23