CVE-2026-15572
The "Allowed Protocol Mapper Types" policy, which restricts which types of data mappers a client can use, fails to re-validate the mapper type during a client update if the mapper's configuration remains unchanged.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.36%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
A flaw was found in Keycloak's Dynamic Client Registration (DCR) security policy management. The "Allowed Protocol Mapper Types" policy, which restricts which types of data mappers a client can use, fails to re-validate the mapper type during a client update if the mapper's configuration remains unchanged. An attacker with client registration privileges can exploit this by first registering an allowed mapper type with a malicious configuration and then swapping it for a restricted, high-privilege mapper type (such as one that hardcodes administrative roles). This allows the attacker to gain full administrative access to the Keycloak realm.
- CVSS 3.1
- 8.8 HIGHCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 0.36% probability · 29th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-843
- Affected
- redhat/build of keycloak
- Source
- secalert@redhat.com
References
- https://access.redhat.com/errata/RHSA-2026:50846Vendor Advisory
- https://access.redhat.com/errata/RHSA-2026:50847Vendor Advisory
- https://access.redhat.com/errata/RHSA-2026:50848Vendor Advisory
- https://access.redhat.com/errata/RHSA-2026:50849Vendor Advisory
- https://access.redhat.com/security/cve/CVE-2026-15572Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=2499592Issue Tracking, Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.