VDB-341856 · CVE-2026-1190 · Nessus 300554

Red Hat Keycloak SAML Brokering SubjectConfirmationData xml validation

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
4.3	$5k-$25k	0.00

Summaryinfo

A vulnerability was found in Red Hat Keycloak and classified as critical. This impacts the function SubjectConfirmationData of the component SAML Brokering. The manipulation results in an unknown weakness. This vulnerability is identified as CVE-2026-1190. There is not any exploit available.

Detailsinfo

A vulnerability classified as critical has been found in Red Hat Keycloak (the affected version is unknown). Affected is the function SubjectConfirmationData of the component SAML Brokering. CWE is classifying the issue as CWE-112. The product accepts XML from an untrusted source but does not validate the XML against the proper schema. The impact remains unknown. CVE summarizes:

A flaw was found in Keycloak's SAML brokering functionality. When Keycloak is configured as a client in a Security Assertion Markup Language (SAML) setup, it fails to validate the `NotOnOrAfter` timestamp within the `SubjectConfirmationData`. This allows an attacker to delay the expiration of SAML responses, potentially extending the time a response is considered valid and leading to unexpected session durations or resource consumption.

The advisory is shared for download at bugzilla.redhat.com. This vulnerability is traded as CVE-2026-1190. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $5k-$25k (estimation calculated on 03/06/2026).

The vulnerability scanner Nessus provides a plugin with the ID 300554 (Keycloak < 26.5.4 Multiple Vulnerabilities), which helps to determine the existence of the flaw in a target environment.

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

The vulnerability is also documented in the databases at Tenable (300554) and CERT Bund (WID-SEC-2026-0147). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Affected

Open Source Keycloak

Productinfo

Vendor

Red Hat

Name

Keycloak

License

open-source

Website

Vendor: https://www.redhat.com/

CPE 2.3info

🔒

CPE 2.2info

🔒

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.3
VulDB Meta Temp Score: 4.3

VulDB Base Score: 5.5
VulDB Temp Score: 5.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 3.1
CNA Vector: 🔒

CVSSv2info

AV	AC	Au	C	I	A
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💳	💳	💳	💳	💳	💳
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Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Xml validation
CWE: CWE-112
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Nessus ID: 300554
Nessus Name: Keycloak < 26.5.4 Multiple Vulnerabilities

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

01/19/2026 Advisory disclosed
01/19/2026 +0 days VulDB entry created
03/06/2026 +46 days VulDB entry last update

Sourcesinfo

Vendor: redhat.com

Advisory: bugzilla.redhat.com
Status: Confirmed

CVE: CVE-2026-1190 (🔒)
GCVE (CVE): GCVE-0-2026-1190
GCVE (VulDB): GCVE-100-341856
CERT Bund: WID-SEC-2026-0147 - Keycloak (SAML brokering): Schwachstelle ermöglicht Manipulation von Dateien

Entryinfo

Created: 01/19/2026 19:54
Updated: 03/06/2026 14:25
Changes: 01/19/2026 19:54 (48), 01/20/2026 11:51 (7), 01/28/2026 13:04 (13), 03/04/2026 23:59 (2), 03/06/2026 14:25 (1)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.