Keycloak on Red Hat authentication bypass

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
4.3$0-$5k0.00

Summaryinfo

A vulnerability was found in Keycloak on Red Hat and classified as problematic. Impacted is an unknown function. Executing a manipulation can lead to authentication bypass. This vulnerability is registered as CVE-2026-9798. It is possible to launch the attack remotely. No exploit is available.

Detailsinfo

A vulnerability classified as problematic was found in Keycloak on Red Hat (the affected version is unknown). This vulnerability affects an unknown code. The manipulation with an unknown input leads to a authentication bypass vulnerability. The CWE definition for the vulnerability is CWE-305. The authentication algorithm is sound, but the implemented mechanism can be bypassed as the result of a separate weakness that is primary to the authentication error. As an impact it is known to affect confidentiality. CVE summarizes:

A flaw was found in Keycloak, an open-source identity and access management solution. When a user account is temporarily locked due to repeated failed login attempts, an attacker with valid client credentials can exploit the Client-Initiated Backchannel Authentication (CIBA) flow to bypass this brute-force protection. This allows continued authentication attempts and token issuance even when the account should be locked, potentially enabling further unauthorized access attempts.

The advisory is shared for download at access.redhat.com. This vulnerability was named CVE-2026-9798 since 05/28/2026. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. Successful exploitation requires user interaction by the victim. There are neither technical details nor an exploit publicly available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 05/28/2026).

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 EUVD (EUVD-2026-32717). Once again VulDB remains the best source for vulnerability data.

Productinfo

Name

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.3
VulDB Meta Temp Score: 4.3

VulDB Base Score: 4.3
VulDB Temp Score: 4.3
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 4.3
CNA Vector (redhat): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Authentication bypass
CWE: CWE-305 / CWE-287
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

05/28/2026 Advisory disclosed
05/28/2026 +0 days CVE reserved
05/28/2026 +0 days VulDB entry created
05/28/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: access.redhat.com
Status: Confirmed

CVE: CVE-2026-9798 (🔒)
GCVE (CVE): GCVE-0-2026-9798
GCVE (VulDB): GCVE-100-366580
EUVD: 🔒

Entryinfo

Created: 05/28/2026 08:36
Updated: 05/28/2026 10:25
Changes: 05/28/2026 08:36 (59), 05/28/2026 10:25 (1)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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