Red Hat Keycloak/Single Sign-On Micrometer user-event metrics listener memory allocation

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.6$0-$5k1.73-

Summaryinfo

A vulnerability, which was classified as critical, was found in Red Hat Keycloak and Single Sign-On. This vulnerability affects unknown code of the component Micrometer user-event metrics listener. The manipulation results in memory allocation. This vulnerability is cataloged as CVE-2026-101333. The attack may be launched remotely. There is no exploit available.

Detailsinfo

A vulnerability classified as critical has been found in Red Hat Keycloak and Single Sign-On (affected version not known). Affected is some unknown functionality of the component Micrometer user-event metrics listener. The manipulation with an unknown input leads to a memory allocation vulnerability. CWE is classifying the issue as CWE-789. The product allocates memory based on an untrusted, large size value, but it does not ensure that the size is within expected limits, allowing arbitrary amounts of memory to be allocated. This is going to have an impact on availability. CVE summarizes:

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.

The advisory is shared for download at access.redhat.com. This vulnerability is traded as CVE-2026-101333 since 09/28/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. There are neither technical details nor an exploit publicly available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 09/28/2026).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Vendor

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License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.6
VulDB Meta Temp Score: 5.6

VulDB Base Score: 7.5
VulDB Temp Score: 7.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 3.7
CNA Vector (redhat): 🔒

CVSSv2info

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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Memory allocation
CWE: CWE-789 / CWE-400 / CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

09/28/2026 Advisory disclosed
09/28/2026 +0 days CVE reserved
09/28/2026 +0 days VulDB entry created
09/28/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: redhat.com

Advisory: access.redhat.com
Status: Not defined

CVE: CVE-2026-101333 (🔒)
GCVE (CVE): GCVE-0-2026-101333
GCVE (VulDB): GCVE-100-411084

Entryinfo

Created: 09/28/2026 17:02
Changes: 09/28/2026 17:02 (60)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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