SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2026-9689

When a client application is configured to accept broad redirect Uniform Resource Identifiers (URIs), a remote attacker can manipulate the authentication process by crafting a special web address.

MEDIUM 4.2EPSS 0.32%

Does this matter?

Lower severity and a low EPSS score (0.32%). Track it; it rarely justifies an emergency change on its own.

Description

A flaw was found in Keycloak, an open-source identity and access management solution. When a client application is configured to accept broad redirect Uniform Resource Identifiers (URIs), a remote attacker can manipulate the authentication process by crafting a special web address. If a user clicks this link, the client application might incorrectly prioritize attacker-controlled information over legitimate data. This vulnerability, known as HTTP parameter pollution, could allow an attacker to bypass security measures or gain unauthorized access to resources.

CVSS 3.1
4.2 MEDIUMCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N
EPSS
0.32% probability · 25th percentile
CISA KEV
Not listed
Weakness
CWE-1288
Affected
redhat/build of keycloak
Source
secalert@redhat.com

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.