CVE-2023-6291: A flaw was found in the redirect_uri validation logic in Keycloak

This month

HIGH 7.1WATCHLISTUPGRADEDOWNGRADEDOWNGRADE

CVE-2023-6291 is a high-severity flaw (CVSS 7.1) affecting keycloak, single sign-on, openshift container platform. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

A flaw was found in the redirect_uri validation logic in Keycloak. This issue may allow a bypass of otherwise explicitly allowed hosts. A successful attack may lead to an access token being stolen, making it possible for the attacker to impersonate other users.

Why this priority

High severity
On your watchlist

A fixed release or distro patch exists.

Risk facts

CVSS score	7.1 (High)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	Required
EPSS exploit chance	0.9% (top 39%)
CISA exploited list	No
Weakness	CWE-601
Published	2024-01-26
Last modified	2026-09-22

Publisher (CNA): Red Hat, Inc. · Vendor: redhat

Last updated 2026-09-22 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2024-01-26 15:15 UTCPublished CVE record published
2026-09-22 04:17 UTCUpdated Record last modified

redhat keycloak UPGRADE

Affected: < 22.0.7

Fixed in: 22.0.7

Safe to downgrade to: no unaffected older release

1. Check installed version

apt-cache policy keycloak || rpm -q keycloak || keycloak --version

2. UPGRADE to 22.0.7 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade keycloak

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade keycloak

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

redhat single sign-on DOWNGRADE

Affected: all versions · 7.6

Fixed in: no fixed release known

Safe to downgrade to: a release before 7.6

1. Check installed version

apt-cache policy single-sign-on || rpm -q single-sign-on || single-sign-on --version

2. No fixed release: DOWNGRADE to a release before 7.6 (Debian / Ubuntu)

apt-cache madison single-sign-on sudo apt install single-sign-on=<VERSION_BEFORE_7.6> sudo apt-mark hold single-sign-on

2. No fixed release: DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list single-sign-on sudo dnf downgrade single-sign-on-<VERSION_BEFORE_7.6> sudo dnf versionlock add single-sign-on

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

redhat openshift container platform DOWNGRADE

Affected: 4.11 · 4.12

Fixed in: no fixed release known

Safe to downgrade to: a release before 4.11

1. Check installed version

apt-cache policy openshift-container-platform || rpm -q openshift-container-platform || openshift-container-platform --version

2. No fixed release: DOWNGRADE to a release before 4.11 (Debian / Ubuntu)

apt-cache madison openshift-container-platform sudo apt install openshift-container-platform=<VERSION_BEFORE_4.11> sudo apt-mark hold openshift-container-platform

2. No fixed release: DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list openshift-container-platform sudo dnf downgrade openshift-container-platform-<VERSION_BEFORE_4.11> sudo dnf versionlock add openshift-container-platform

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

redhat openshift container platform for ibm z DOWNGRADE

Affected: 4.9 · 4.10

Fixed in: no fixed release known

Safe to downgrade to: a release before 4.9

1. Check installed version

apt-cache policy openshift-container-platform-for-ibm-z || rpm -q openshift-container-platform-for-ibm-z || openshift-container-platform-for-ibm-z --version

2. No fixed release: DOWNGRADE to a release before 4.9 (Debian / Ubuntu)

apt-cache madison openshift-container-platform-for-ibm-z sudo apt install openshift-container-platform-for-ibm-z=<VERSION_BEFORE_4.9> sudo apt-mark hold openshift-container-platform-for-ibm-z

2. No fixed release: DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list openshift-container-platform-for-ibm-z sudo dnf downgrade openshift-container-platform-for-ibm-z-<VERSION_BEFORE_4.9> sudo dnf versionlock add openshift-container-platform-for-ibm-z

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

redhat openshift container platform for linuxone DOWNGRADE

Affected: 4.9 · 4.10

Fixed in: no fixed release known

Safe to downgrade to: a release before 4.9

1. Check installed version

apt-cache policy openshift-container-platform-for-linuxone || rpm -q openshift-container-platform-for-linuxone || openshift-container-platform-for-linuxone --version

2. No fixed release: DOWNGRADE to a release before 4.9 (Debian / Ubuntu)

apt-cache madison openshift-container-platform-for-linuxone sudo apt install openshift-container-platform-for-linuxone=<VERSION_BEFORE_4.9> sudo apt-mark hold openshift-container-platform-for-linuxone

2. No fixed release: DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list openshift-container-platform-for-linuxone sudo dnf downgrade openshift-container-platform-for-linuxone-<VERSION_BEFORE_4.9> sudo dnf versionlock add openshift-container-platform-for-linuxone

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

redhat openshift container platform for power DOWNGRADE

Affected: 4.9 · 4.10

Fixed in: no fixed release known

Safe to downgrade to: a release before 4.9

1. Check installed version

apt-cache policy openshift-container-platform-for-power || rpm -q openshift-container-platform-for-power || openshift-container-platform-for-power --version

2. No fixed release: DOWNGRADE to a release before 4.9 (Debian / Ubuntu)

apt-cache madison openshift-container-platform-for-power sudo apt install openshift-container-platform-for-power=<VERSION_BEFORE_4.9> sudo apt-mark hold openshift-container-platform-for-power

2. No fixed release: DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list openshift-container-platform-for-power sudo dnf downgrade openshift-container-platform-for-power-<VERSION_BEFORE_4.9> sudo dnf versionlock add openshift-container-platform-for-power

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2023-6291?

keycloak: upgrade to 22.0.7; single sign-on: downgrade or apply the listed mitigation; openshift container platform: downgrade or apply the listed mitigation. Exact commands for each OS are on this page.

Is CVE-2023-6291 being exploited?

CVE-2023-6291 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2023-6291 affect?

CVE-2023-6291 affects keycloak, single sign-on, openshift container platform. Severity is high (CVSS 7.1). A flaw was found in the redirect_uri validation logic in Keycloak. This issue may allow a bypass of otherwise explicitly allowed hosts. A successful attack may lead to an access token being stolen, making it possible for the attacker to imp

How urgent is CVE-2023-6291?

Priority 45/100. High severity; On your watchlist

Software pages

Keycloak vulnerabilities · Red Hat OpenShift vulnerabilities

Related CVEs

CVE-2023-6927 MEDIUM 4.6 MITIGATE DOWNGRADE A flaw was found in Keycloak
CVE-2023-6563 HIGH 7.7 UPGRADE DOWNGRADE An unconstrained memory consumption vulnerability was discovered in Keycloak
CVE-2023-6134 MEDIUM 4.6 UPGRADE UPGRADE A flaw was found in Keycloak that prevents certain schemes in redirects, but permits them if a wildcard is app
CVE-2025-8419 MEDIUM 5.3 MITIGATE A vulnerability was found in Keycloak-services
CVE-2025-7365 HIGH 7.1 MITIGATE A flaw was found in Keycloak

References

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