CVE-2023-6841Network attack vector

Service interruption via unbounded attribute responses

Published Sep 10, 2024 · Updated Nov 8, 2025

Denial of service in Keycloak before 24.0.0 and Red Hat Single Sign-On 7 allows remote attackers to exhaust server resources. User, group, and role objects accept an unbounded number of attributes, and list endpoints serialize many rows containing long attribute values. Repeated unauthenticated HTTP requests to those list endpoints can consume enough resources to interrupt the identity service.

CVSS severity7.5
High
EPSS probability0.74%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Denial of service in Keycloak before 24.0.0 and Red Hat Single Sign-On 7 allows remote attackers to exhaust server resources. User, group, and role objects accept an unbounded number of attributes, and list endpoints serialize many rows containing long attribute values. Repeated unauthenticated HTTP requests to those list endpoints can consume enough resources to interrupt the identity service.

The record

CVE
CVE-2023-6841
Published
Sep 10, 2024
Updated
Nov 8, 2025
Vendor
Red Hat
Product
Red Hat Single Sign-On 7
Classifications
CWE-231, T1499.003
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 10, 2024CVE publishedPublication date reported by the CVE source.
  2. Nov 8, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected versions are unavailable in this record. Check the vendor advisory for version and patch details.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Red Hat · Red Hat Single Sign-On 7Affected versions are unavailable in this record.
Keycloak · Keycloakversion=0 <24.0.0

Published CVSS scores

7.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
7.1GitHub Advisory DatabaseCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
7.5Red HatCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-231Improper Handling of Extra Values
T1499.003Application Exhaustion Flood

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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