Red Hat build of Keycloak 26.4 · Vulnerability
cve-program · CVE-2026-18217
PublishedA flaw was found in the SAML protocol implementation of Keycloak, an open-source identity and access management solution. The issue occurs when Keycloak handles SAML authentication requests using the HTTP-Redirect binding. If a client is configured with a wildcard redirect URL, an attacker can craft a request that includes malicious parameters. When a user authenticates, Keycloak appends its legitimate response to the attacker's parameters. This can cause some service providers to process the attacker's data instead of the real login information, potentially leading to a user being logged into the wrong account.
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cve-program · CVE-2026-18217
PublishedKeycloak-services: keycloak-services: saml http-redirect binding response preserves query string leading to parameter pollution
A flaw was found in the SAML protocol implementation of Keycloak, an open-source identity and access management solution. The issue occurs when Keycloak handles SAML authentication requests using the HTTP-Redirect binding. If a client is configured with a wildcard redirect URL, an attacker can craft a request that includes malicious parameters. When a user authenticates, Keycloak appends its legitimate response to the attacker's parameters. This can cause some service providers to process the attacker's data instead of the real login information, potentially leading to a user being logged into the wrong account.
- Source published
- 31 Jul 2026 06:38:25 UTC
- Source modified
- 6 Nov 2026 17:32:51 UTC
- Saved here
- 6 Nov 2026 19:02:40 UTC
- Source terms
- CVE Program Terms of Use
Original source record · Cite this exact observation · Complete original publisher JSON
Source: cve-program · CVE Program Terms of Use. The publisher's wording is preserved. ChangeIntel groups the information and labels changes. The JSON record includes additional source fields.
CVSS 3.1 · 3.4 CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:N/I:L/A:N