VulnerabilityPublished 19 May 2026Updated 20 May 2026

CVE-2026-7571: Red Hat build of Keycloak 26.4 · External Control of Assumed-Immutable Web Parameter

Affects Red Hat build of Keycloak 26.4Source CVE Database V5

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Not known to be exploited · CVSS 7.1 High.

Data as of 30 Oct 2026, 11:52 UTC

CVSS 3.1 base score

7.1High

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

EPSS: 0.4% chance of exploitation in 30 days – higher than 35% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

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

Attack Vector: Network
Attack Complexity: Low
Privileges Required: Low
User Interaction: None
Scope: Unchanged
Confidentiality: High
Integrity: Low
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: Low: Modification of data is possible, but the attacker does not have control over the consequence of a modification, or the amount of modification is limited. The data modification does not have a direct, serious impact on 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 19 May 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: 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 30 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.
Weaponized: A Metasploit exploit module or Exploit-DB entry exists (Metasploit scanner modules do not count), 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

Affected software

Product	Affected	Fixed in
Mavenorg.keycloak/keycloak`pkg:maven/org.keycloak/keycloak`Other threats	Affected =26.4	Fixed in–

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AI-suggested

Red Hat has released updated packages for Red Hat build of Keycloak version 26.4.12 that address CVE-2026-7571 along with other vulnerabilities. Users should back up their existing installations and apply the official update from the Red Hat Customer Portal. No temporary or alternative mitigations are documented; applying the official patch is the recommended remediation.

Description

CVE-2026-7571 is a vulnerability in Red Hat build of Keycloak 26.4 where a low-privilege user can bypass a security control designed to disable the implicit flow in OpenID Connect clients. By manipulating client data during a session restart, the attacker can obtain access tokens that should be unavailable. These tokens may also be exposed in server logs, proxy logs, and HTTP Referrer headers, leading to sensitive information disclosure. The vulnerability has a CVSS score of 7.1, indicating high severity. Red Hat has released updated packages (Keycloak 26.4.12) addressing this and other related security issues. Users are advised to apply these updates after backing up their installations.

Impact

Successful exploitation allows a low-privilege attacker to bypass security controls disabling the implicit flow in OIDC clients, resulting in unauthorized access token disclosure. This can lead to sensitive information exposure through logs and HTTP headers. The confidentiality impact is high, integrity impact is low, and availability is not affected. No known exploits in the wild have been reported at this time.

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 26 May 2026, 20:40 UTC

Technical details

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