Free and open · new CVEs checked every 20 minutesStatusRSSOpen dataContact

CVE-2026-15573: A flaw was found in Keycloak's Authorization Services

43
This month
HIGH 8.1WATCHLISTUPGRADEDOWNGRADEMITIGATE

CVE-2026-15573 is a high-severity flaw (CVSS 8.1) affecting build of keycloak, data grid, jboss enterprise application platform expansion pack. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

A flaw was found in Keycloak's Authorization Services. The component responsible for matching request paths to security policies (PathMatcher) does not properly normalize URIs before comparison. By adding extra characters like a trailing slash or matrix parameters to a URL, an attacker can trick the system into applying a less restrictive security policy than intended. This allows an authenticated user to access administrative or restricted areas

Why this priority

  • High severity
  • On your watchlist

A fixed release or distro patch exists.

Risk facts

CVSS score8.1 (High)
Attack vectorNetwork (remote)
Attack complexityLow
Privileges neededLow
User interactionNone
EPSS exploit chance0.5% (top 60%)
CISA exploited listNo
WeaknessCWE-551, CWE-178
Published2026-08-05
Last modified2026-08-31
Publisher (CNA): Red Hat, Inc. · Vendor: redhat

Share: LinkedIn · X · Reddit

Last updated 2026-08-31 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

redhat build of keycloak UPGRADE
Affected: >= 26.4 and < 26.4.14 · >= 26.6 and < 26.6.5
Fixed in: 26.4.14, 26.6.5
Safe to downgrade to: a release before 26.4
1. Check installed version
apt-cache policy build-of-keycloak || rpm -q build-of-keycloak || build-of-keycloak --version
2. UPGRADE to 26.4.14 (Debian / Ubuntu)
sudo apt update && sudo apt install --only-upgrade build-of-keycloak
2. UPGRADE (RHEL / Amazon Linux / Fedora)
sudo dnf upgrade build-of-keycloak
Note
Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.
3. If no update is available yet, DOWNGRADE to a release before 26.4 (Debian / Ubuntu)
apt-cache madison build-of-keycloak sudo apt install build-of-keycloak=<VERSION_BEFORE_26.4> sudo apt-mark hold build-of-keycloak
3. If no update is available yet, DOWNGRADE (RHEL / Amazon Linux / Fedora)
dnf --showduplicates list build-of-keycloak sudo dnf downgrade build-of-keycloak-<VERSION_BEFORE_26.4> sudo dnf versionlock add build-of-keycloak
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 data grid DOWNGRADE
Affected: 8.0
Fixed in: no fixed release known
Safe to downgrade to: a release before 8.0
1. Check installed version
apt-cache policy data-grid || rpm -q data-grid || data-grid --version
2. No fixed release: DOWNGRADE to a release before 8.0 (Debian / Ubuntu)
apt-cache madison data-grid sudo apt install data-grid=<VERSION_BEFORE_8.0> sudo apt-mark hold data-grid
2. No fixed release: DOWNGRADE (RHEL / Amazon Linux / Fedora)
dnf --showduplicates list data-grid sudo dnf downgrade data-grid-<VERSION_BEFORE_8.0> sudo dnf versionlock add data-grid
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 jboss enterprise application platform expansion pack MITIGATE
Affected: all versions
Fixed in: no fixed release known
Safe to downgrade to: no unaffected older release
1. Check installed version
apt-cache policy jboss-enterprise-application-platform-expansion-pack || rpm -q jboss-enterprise-application-platform-expansion-pack || jboss-enterprise-application-platform-expansion-pack --version
No fixed or unaffected release known
Apply the vendor mitigation from the advisory, disable the affected feature, or restrict network access.
redhat single sign-on DOWNGRADE
Affected: 7.0
Fixed in: no fixed release known
Safe to downgrade to: a release before 7.0
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 7.0 (Debian / Ubuntu)
apt-cache madison single-sign-on sudo apt install single-sign-on=<VERSION_BEFORE_7.0> 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_7.0> 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.
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-2026-15573?

build of keycloak: upgrade to 26.4.14, 26.6.5; data grid: downgrade or apply the listed mitigation; jboss enterprise application platform expansion pack: mitigate or apply the listed mitigation. Exact commands for each OS are on this page.

Is CVE-2026-15573 being exploited?

CVE-2026-15573 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-2026-15573 affect?

CVE-2026-15573 affects build of keycloak, data grid, jboss enterprise application platform expansion pack. Severity is high (CVSS 8.1). A flaw was found in Keycloak's Authorization Services. The component responsible for matching request paths to security policies (PathMatcher) does not properly normalize URIs before comparison. By adding extra characters like a trailing sl

How urgent is CVE-2026-15573?

Priority 43/100. High severity; On your watchlist

Software pages

Keycloak vulnerabilities · JBoss and WildFly vulnerabilities

Related CVEs

References

← Back to latest CVEs

Get the weekly exploited-CVE digest by emailThe CVEs being attacked this week and how to fix them. No spam, unsubscribe any time.