# CVE-2026-101333: Keycloak-services: keycloak-services: unbounded metric series creation via idp tag on broker login endpoint

> An unauthenticated attacker can cause excessive memory consumption and degrade performance by sending arbitrary requests to the broker login endpoint when specific metrics are enabled.

- **Severity:** Low 3.7 (`CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 28 Sep 2026
- **Updated:** 28 Sep 2026
- **Also known as:** GHSA-5fh4-qp8q-2wxm, UBUNTU-CVE-2026-101333

## What is CVE-2026-101333?

CVE-2026-101333 is a low-severity denial of service vulnerability in Red Hat Build of Keycloak, published on 28 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A flaw was found in the Micrometer user-event metrics listener of Keycloak, a solution for integrated identity and access management. The issue occurs when the listener is configured to include the idp tag. An unauthenticated attacker can send requests to the identity broker login endpoint using arbitrary provider aliases, causing the system to create an unlimited number of metric time series. This can lead to excessive memory consumption and degrade the performance of both the server and its monitoring tools.

Weakness: CWE-770 (Allocation of Resources Without Limits or Throttling)

## Which versions are affected by CVE-2026-101333?


## How do I fix CVE-2026-101333?

No fix has been published for CVE-2026-101333 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-101333 being exploited?

There is no known exploitation of CVE-2026-101333 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-101333 and fix it if it is affected.

What it is: CVE-2026-101333 is a low-severity denial of service vulnerability in Red Hat Build of Keycloak, published on 28 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-101333 in the wild and no public exploit code.

Affected product: Red Hat Build of Keycloak. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-101333/ (Markdown: https://insights.sbomify.com/CVE-2026-101333/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-101333
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-101333
- OSV: https://osv.dev/vulnerability/CVE-2026-101333

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-101333/
Summaries are generated and may contain mistakes; the official description above is the record.