Red Hat Keycloak UserResource private personal information

Summaryinfo

A vulnerability was found in Red Hat Keycloak. It has been classified as problematic. This issue affects some unknown processing of the component UserResource. This manipulation causes private personal information. The identification of this vulnerability is CVE-2026-3911. It is possible to initiate the attack remotely. There is no exploit available.

Detailsinfo

A vulnerability classified as problematic was found in Red Hat Keycloak (unknown version). Affected by this vulnerability is an unknown code block of the component UserResource. The manipulation with an unknown input leads to a private personal information vulnerability. The CWE definition for the vulnerability is CWE-359. The product does not properly prevent a person's private, personal information from being accessed by actors who either (1) are not explicitly authorized to access the information or (2) do not have the implicit consent of the person about whom the information is collected. As an impact it is known to affect confidentiality. The summary by CVE is:

A flaw was found in Keycloak. An authenticated user with the view-users role could exploit a vulnerability in the UserResource component. By accessing a specific administrative endpoint, this user could improperly retrieve user attributes that were configured to be hidden. This unauthorized information disclosure could expose sensitive user data.

It is possible to read the advisory at access.redhat.com. This vulnerability is known as CVE-2026-3911 since 03/11/2026. The exploitation appears to be easy. The attack can be launched remotely. Additional levels of successful authentication are needed for exploitation. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 03/17/2026). The attack technique deployed by this issue is T1589 according to MITRE ATT&CK.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at CERT Bund (WID-SEC-2026-0693). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Affected

• Open Source Keycloak

Productinfo

Vendor

• Red Hat

Name

• Keycloak

License

• open-source

Website

• Vendor: https://www.redhat.com/

CPE 2.3info

• 🔒

CPE 2.2info

• 🔒

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Discussion