CVE-2026-18211

mediumpriority · track · 22EPSS 0.003 · 23 %ileDEEUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.31% (23rd) EPSS

CVSS 5.4 · medium

Is it mine?

2 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · cert_bund · nvd

EPSS · scored 2026-10-27

A flaw was found in the secure-client-uris client policy executor within Keycloak core services. This component is responsible for enforcing security requirements on client configurations, such as requiring encrypted connections for redirect URIs. Due to an improper check that only looks at the start of a web address rather than properly verifying the host, an attacker can bypass these security restrictions by using a specially crafted domain name. This could allow an attacker to intercept sensitive authentication codes over unencrypted connections.

cvss

Technical severity, 0–10. One row per scoring source.

5.4

010

base score 0–10 · higher = more severe · hover a vector to decode

v3.15.4mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:Nprimary · NVD / NIST USexploitability 2.8 · impact 2.5

v3.14.2mediumCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:Nsecondary · ENISA EU

v3.14.2mediumCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:Nsecondary · secalert@redhat.com USexploitability 1.6 · impact 2.5

v3.15mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N/E:Usecondary · CVSS-BT (t0sche)

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Trackcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-20US

affected products (2)

Products and version ranges known to be affected.

Open Source Keycloakall versionscert_bundDEcpe:/a:keycloak:keycloak:-
redhat build of keycloakall versionsnvdUScpe:2.3:a:redhat:build_of_keycloak:*:*:*:*:*:*:*:*

advisories (1)

Vendor and ecosystem advisories describing this.

WID-SEC-W-2026-2614Keycloak: Mehrere SchwachstellenDeutsch2026-08-02csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in Keycloak ausnutzen, um seine Privilegien zu erhöhen, Sicherheitsmaßnahmen zu umgehen, Daten zu manipulieren und sensible Informationen offenzulegen.

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd cert_bund nvd NVD CVE.org MITRE

published 2026-07-31modified 2026-08-07

references (6)

External citations — patches, advisories, analysis.

scry

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