Keycloak on Red Hat Access Token external control of assumed-immutable web parameter

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.7$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as critical, has been found in Keycloak on Red Hat. This vulnerability affects unknown code of the component Access Token Handler. The manipulation leads to external control of assumed-immutable web parameter. This vulnerability is documented as CVE-2026-7571. The attack can be initiated remotely. There is not any exploit available.

Detailsinfo

A vulnerability was found in Keycloak on Red Hat (affected version unknown) and classified as critical. This issue affects an unknown functionality of the component Access Token Handler. The manipulation with an unknown input leads to a external control of assumed-immutable web parameter vulnerability. Using CWE to declare the problem leads to CWE-472. The web application does not sufficiently verify inputs that are assumed to be immutable but are actually externally controllable, such as hidden form fields. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

A flaw was found in Keycloak. A low-privilege user, with knowledge of user credentials and client ID, can bypass a security control intended to disable the implicit flow in OpenID Connect (OIDC) clients. By manipulating client data during a session restart, an attacker can obtain an access token that should not be available. This vulnerability can also lead to the exposure of these access tokens in server logs, proxy logs, and HTTP Referrer headers, resulting in sensitive information disclosure.

It is possible to read the advisory at access.redhat.com. The identification of this vulnerability is CVE-2026-7571 since 05/01/2026. The exploitation is known to be easy. The attack may be initiated remotely. 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 05/20/2026).

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 CERT Bund (WID-SEC-2026-1612). Be aware that VulDB is the high quality source for vulnerability data.

Affected

  • Red Hat Enterprise Linux
  • Open Source Keycloak

Productinfo

Name

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.7
VulDB Meta Temp Score: 6.7

VulDB Base Score: 6.3
VulDB Temp Score: 6.3
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 7.1
CNA Vector (redhat): 🔒

CVSSv2info

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

Exploitinginfo

Class: External control of assumed-immutable web parameter
CWE: CWE-472
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

05/01/2026 CVE reserved
05/19/2026 +18 days Advisory disclosed
05/19/2026 +0 days VulDB entry created
05/20/2026 +1 days VulDB entry last update

Sourcesinfo

Advisory: access.redhat.com
Status: Confirmed

CVE: CVE-2026-7571 (🔒)
GCVE (CVE): GCVE-0-2026-7571
GCVE (VulDB): GCVE-100-364631
CERT Bund: WID-SEC-2026-1612 - Keycloak: Mehrere Schwachstellen

Entryinfo

Created: 05/19/2026 15:43
Updated: 05/20/2026 14:39
Changes: 05/19/2026 15:43 (60), 05/20/2026 14:39 (7)
Complete: 🔍
Cache ID: 216::103

Be aware that VulDB is the high quality source for vulnerability data.

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