CyberSecBulletin
CVE-2026-15572NVD status: Analyzed

Red Hat build of Keycloak 26.4: Access of Resource Using Incompatible Type

CVE-2026-15572 is a high-severity access of resource using incompatible type vulnerability in Red Hat build of Keycloak 26.4 from Red Hat, with a CVSS 3.1 base score of 8.8 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. There is no confirmed exploitation so far. EPSS estimates a 0.65% chance of exploitation within 30 days, higher than 52% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Build Of Keycloak to 26.4.14 or 26.6.5, whichever matches your release line, or a later version.
  2. Read the advisory on access.redhat.com for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
Red HatRed Hat build of Keycloak 26.4Not specified in the recordNot stated
Red HatRed Hat build of Keycloak 26.4.14Not specified in the recordNot stated
Red HatRed Hat build of Keycloak 26.6Not specified in the recordNot stated
Red HatRed Hat build of Keycloak 26.6.5Not specified in the recordNot stated
Red HatBuild Of Keycloak26.4 up to, but not including, 26.4.14; 26.6 up to, but not including, 26.6.526.4.14, 26.6.5

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by CNA (redhat.com).

Official 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.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Access of Resource Using Incompatible Type

The product allocates or initializes a resource such as a pointer, object, or variable using one type, but it later accesses that resource using a type that is incompatible with the original type.

More Access of Resource Using Incompatible Type vulnerabilities (CWE-843)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in Red Hat build of Keycloak 26.4

All Red Hat build of Keycloak 26.4 vulnerabilities

Recent Access of Resource Using Incompatible Type vulnerabilities

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