How severe is CVE-2026-4636?

No CVSS score has been assigned to CVE-2026-4636 yet. Review the advisory details and affected package list to assess your exposure.

Which packages are affected by CVE-2026-4636?

CVE-2026-4636 affects the following packages: keycloak (Bitnami). Ecosystems affected: Bitnami.

How do I fix CVE-2026-4636?

Update keycloak to 26.2.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-4636 is resolved across your whole dependency graph.

How do I detect CVE-2026-4636 in my Bitnami dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for keycloak, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2026-4636 if there is no patch (or I can't update yet)?

If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

How does O3 Security protect against CVE-2026-4636?

O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2026-4636 can be triaged on real exposure rather than presence alone.

Is CVE-2026-4636 actively exploited in the wild?

No public exploit code has been indexed for CVE-2026-4636 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2026-4636?

CVE-2026-4636 has an EPSS (Exploit Prediction Scoring System) score of 0.3%, placing it in the 28th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2026-4636?

CVE-2026-4636 is classified as CWE-551 (CWE-551). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2026-4636 published, and has it been updated?

CVE-2026-4636 was published on August 25, 2026 and was last updated on September 8, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

CVE-2026-4636: keycloak

Exploitation Status

No confirmed exploitation observed yet

A successful exploit gives an attacker total control of the affected component, not partial access.
CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.

Exploitation and automatability from CISA’s SSVC triage for CVE-2026-4636.

EPSS Exploitation Probability

via FIRST.org ↗

0.3%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs28th percentile — riskier than 28% of all scored CVEsHighest risk

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

Real-World Exposure

1 pkg affected

📦keycloak

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Bitnami packages — download data is not available via public APIs for these ecosystems.

Description

A flaw was found in Keycloak. An authenticated user with the uma_protection role can bypass User-Managed Access (UMA) policy validation. This allows the attacker to include resource identifiers owned by other users in a policy creation request, even if the URL path specifies an attacker-owned resource. Consequently, the attacker gains unauthorized permissions to victim-owned resources, enabling them to obtain a Requesting Party Token (RPT) and access sensitive information or perform unauthorized actions.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
📦Bitnami	`keycloak`	≥ 26.2.0&&< 26.2.1	26.2.1

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for keycloak, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update keycloak to 26.2.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-4636 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2026-4636 can be triaged on real exposure rather than presence alone.

Tailored to CVE-2026-4636. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Fixing This On Your OS

If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.

Red HatImportant

This Important vulnerability in Keycloak allows an authenticated user with the `uma_protection` role to bypass User-Managed Access (UMA) policy validation. Exploitation requires that victim users have created UMA-protected resources with `ownerManagedAccess` enabled and that authorization services are enabled on the…

Product	Fixed in	Advisory
Red Hat build of Keycloak 26.2	`rhbk/keycloak-operator-bundle:26.2.15-1`	RHSA-2026:6476
Red Hat build of Keycloak 26.2.15	`rhbk/keycloak-rhel9`	RHSA-2026:6475
Red Hat build of Keycloak 26.4	`rhbk/keycloak-operator-bundle:26.4.11-1`	RHSA-2026:6478
Red Hat build of Keycloak 26.4.11	`rhbk/keycloak-rhel9`	RHSA-2026:6477

Frequently Asked Questions

A flaw was found in Keycloak. An authenticated user with the uma_protection role can bypass User-Managed Access (UMA) policy validation. This allows the attacker to include resource identifiers owned by other users in a policy creation request, even if the URL path specifies an attacker-owned resource. Consequently, the attacker gains unauthorized permissions to victim-owned resources, enabling them to obtain a Requesting Party Token (RPT) and access sensitive information or perform unauthorized actions.

O3 Security · Impact-Aware SCA

Is CVE-2026-4636 in your dependencies?

O3 Security finds CVE-2026-4636 across Bitnami dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.

Scan my dependencies How O3 SCA works

CVE-2026-4636 — keycloak