CVE-2024-3656VulnerabilityPublished 3 Jun 2024Updated 9 Oct 2026

Red Hat Security Advisory: Red Hat build of Keycloak 24.0.5 enhancement and security update

Affects Red HatSource GCVE Database

Mentioned vulnerabilities

CVE-2024-4540

Authoritative record:CVE-2024-3656· High 8.1

Not known to be exploited · public detection template (Nuclei) · CVSS 8.1 High : upgrade Red Hat keycloak to 24.0.5 soon.

Data as of 26 Oct 2026, 12:29 UTC

CVSS 3.1 base score

8.1High

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 3.3% chance of exploitation in 30 days – higher than 88% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 24.0.5

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N

Attack Vector: Network
Attack Complexity: Low
Privileges Required: Low
User Interaction: None
Scope: Unchanged
Confidentiality: High
Integrity: High
Availability: None

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Network: The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed, up to and including the entire Internet. Such a vulnerability is often termed 'remotely exploitable' and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: Low: The attacker is authorized with (i.e., requires) privileges that provide basic user capabilities that could normally affect only settings and files owned by a user. Alternatively, an attacker with Low privileges may have the ability to cause an impact only to non-sensitive resources.
User Interaction: None: The vulnerable system can be exploited without any interaction from any user.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: High: There is total loss of confidentiality, resulting in all resources within the impacted component being divulged to the attacker. Alternatively, access to only some restricted information is obtained, but the disclosed information presents a direct, serious impact.
Integrity: High: There is a total loss of integrity, or a complete loss of protection. For example, the attacker is able to modify any/all files protected by the impacted component. Alternatively, only some files can be modified, but malicious modification would present a direct, serious consequence to the impacted component.
Availability: None: There is no impact to availability within the impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 9 Oct 2024
Detectable: evidence found.
nuclei template: Keycloak < 24.0.5 - Broken Access Control
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Upgrade keycloak to 24.0.5.

Affected software

Product	Affected	Fixed in
GitHubkeycloak`pkg:github/keycloak`Other threats	Affected <24.0.5	Fixed in 24.0.5

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

AI-suggested

Red Hat has released an official security update in version 24.0.5 of their build of Keycloak that addresses this vulnerability. Users should back up their existing installations and apply the update as recommended in the Red Hat advisory RHSA-2024:3575. No additional mitigation steps are indicated beyond applying the official fix.

Description

Red Hat has issued a security advisory for Red Hat build of Keycloak 24.0.5 addressing an exposure of sensitive information in the Pushed Authorization Requests (PAR) KC_RESTART cookie. This vulnerability is tracked as CVE-2024-4540 and is rated with low severity. The advisory recommends updating to the fixed version 24.0.5 to mitigate the issue. Keycloak is a standalone server providing authentication and single sign-on capabilities for web and mobile applications.

Impact

The vulnerability allows exposure of sensitive information in the PAR KC_RESTART cookie, which could lead to information disclosure. However, the severity is rated low by Red Hat Product Security, indicating limited impact or exploitability. There are no known exploits in the wild at this time.

Summary

The Red Hat build of Keycloak 24.0.5 includes a security fix for CVE-2024-4540, which involves the exposure of sensitive information through the Pushed Authorization Requests (PAR) KC_RESTART cookie. This vulnerability could potentially leak sensitive data related to authentication sessions. The advisory references CVE-2024-3656 as well but focuses on the fix for CVE-2024-4540. The update is classified as a low severity security enhancement and is part of the Red Hat security errata RHSA-2024:3575.

CWE-200Exposure of Sensitive Information to an Unauthorized Actor (opens in a new tab)
Class weaknessLikelihood of exploit: HighCWE Top 25 (2025): #20OWASP Top 10 A01:2025: Broken Access Control (opens in a new tab)
The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information.
MITRE discourages mapping vulnerabilities to this broad entry; the root cause is usually a more specific weakness.
Architecture and Design · Separation of Privilege
Compartmentalize the system to have "safe" areas where trust boundaries can be unambiguously drawn. Do not allow sensitive data to go outside of the trust boundary and always be careful when interfacing with a compartment outside of the safe area.
OWASP Cheat Sheets
Error Handling (opens in a new tab)
Logging (opens in a new tab)
Authorization (opens in a new tab)
OWASP ASVS 4.0.3
V8.3.4 (opens in a new tab)
V14.3.3 (opens in a new tab)
V7.3.3 (opens in a new tab)
Attack patterns
Subverting Environment Variable Values (opens in a new tab)
ICMP Echo Request Ping (opens in a new tab)
TCP SYN Scan (opens in a new tab)
Enumerate Mail Exchange (MX) Records (opens in a new tab)
DNS Zone Transfers (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).
CWE-312Cleartext Storage of Sensitive Information (opens in a new tab)
Base weaknessOWASP Top 10 A06:2025: Insecure Design (opens in a new tab)
The product stores sensitive information in cleartext within a resource that might be accessible to another control sphere.
Implementation · System Configuration · Operation
When storing data in the cloud (e.g., S3 buckets, Azure blobs, Google Cloud Storage, etc.), use the provider's controls to encrypt the data at rest.
Implementation · System Configuration · Operation
In some systems/environments such as cloud, the use of "double encryption" (at both the software and hardware layer) might be required, and the developer might be solely responsible for both layers, instead of shared responsibility with the administrator of the broader system/environment.
OWASP Cheat Sheets
Secure Design Principles (opens in a new tab)
OWASP ASVS 4.0.3
V8.1.6 (opens in a new tab)
V8.2.3 (opens in a new tab)
V8.2.2 (opens in a new tab)
Attack patterns
Retrieve Embedded Sensitive Data (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

Community reviews

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 9 Oct 2026, 23:07 UTC

Public exploits and detectiona Nuclei detection template

WeaknessesCWE-200, CWE-312

Technical details

References

Community reviews

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