CVE Tools
Sign in

CVE-2026-18215

Keycloak-services: keycloak-services: microsoft external access-token exchange bypasses configured tenant

Published: Jul 31, 2026Updated: Aug 7, 2026 Sources: CVE List NVDCWE-287
6.8MEDIUM
NVD MITRE
EPSS Score
0.2%
Top 91.5%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available
Self-Check
OpenVAS

Description

Keycloak provides a way to let users log in using Microsoft accounts while restricting access to a specific organization (tenant). A flaw was discovered where this restriction is ignored when using the token exchange feature. This means an attacker with a valid Microsoft token from a completely different organization could gain access to the Keycloak realm, potentially accessing sensitive data or performing unauthorized actions.

No summary for this CVE yet.

CVSS Vector Breakdown

AV:NAC:HPR:LUI:NS:UC:HI:HA:N
Exploitability
AV:NAttack Vector
Network
AC:HAttack Complexity
High
PR:LPrivileges Required
Low
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:HConfidentiality
High
I:HIntegrity
High
A:NAvailability
None
Open in CVSS calculator →

Weaknesses

CWE-287

Affected Products

Red Hat
commercial·USaka redhat
Red Hat Build of Keycloak
Web & CMS Plugins
Red Hat Data Grid 8On-premDatabase
Databases / cache-message-queue
Red Hat JBoss Enterprise Application Platform Expansion PackOn-premOS
Operating Systems / linux-distro
Red Hat Single Sign-On 7On-premSecurity Product
Security Products / identity-access-mgmt
build of keycloakOn-prem
Operating Systems / linux-distro

Exploitability

Official Patch Available
Workaround Available
Is your org exposed to CVE-2026-18215?We can run the check for you — a free external exposure review, no install. Check my exposure

Attack Graph

Products CVE Techniques Tactics

Click technique nodes for MITRE ATT&CK details · drag to pan · Ctrl/⌘ + scroll to zoom, or go fullscreen.

MITRE ATT&CK

2 techniques
Initial Access
View detailed technique mapping

References

https://access.redhat.com/security/cve/CVE-2026-18215
access.redhat.com
https://bugzilla.redhat.com/show_bug.cgi?id=2508309
bugzilla.redhat.com

Unlock Complete Vulnerability Intelligence

Get the full picture for CVE-2026-18215 and every CVE in our database. Create a free account — no credit card required.

Create Free Account
Plain-language analysis
Impact assessment and exploitation scenario in plain English
Attack graph visualization
Interactive attack path and kill chain mapping
Exploit details & PoC links
ExploitDB, Metasploit, GitHub PoCs with direct links
Nuclei scanner templates
Ready-to-use vulnerability scanner templates
Full remediation guide
Patch instructions, workarounds, and compliance impact
Interactive AI chat
Ask questions about this vulnerability in natural language
Related vulnerabilities
Semantically similar CVEs and attack patterns
REST API & MCP access
Integrate vulnerability data into your workflows