CVE-2026-16443

Status: AnalyzedCritical (9.1)—

A flaw was found in the SAML metadata import functionality of the keycloak-services component, which is the core engine for identity brokering in Red Hat Build of Keycloak. When importing identity provider metadata that lacks specific usage attributes for keys, the system incorrectly disables signature validation for SAML responses even if a signing certificate is provided. This issue allows an unauthenticated attacker to forge a SAML response and gain unauthorized access to a user account by knowing their external identifier.

CVSS

Version: 3.1
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Base score: 9.1

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days: 0.26%
Percentile among all scored CVEs: 16
Score date: 10/5/2026

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

🎯 ATT&CK techniques

How this vulnerability is exploited and what the attacker gains, in MITRE ATT&CK terms.

ExploitationT1190 Exploit Public-Facing Applicationinitial access95 %
Primary impactT1078.001 Default Accountsstealth · persistence · privilege escalation · initial access90 %
Secondary impactT1556.003 Pluggable Authentication Modulesdefense impairment · persistence · credential access85 %

Vulnerabilidad de validación en importación de metadatos SAML accesible sin autenticación (AV:N, PR:N). El atacante falsifica respuestas SAML para obtener acceso a cuentas de usuario sin credenciales legítimas, explotando un servicio web expuesto (T1190) e impactando en creación/secuestro de identid

Inferred by our analysis agent from the official description, CVSS vector and CWE, and checked by a supervisor. May contain errors.

🛡️ ATT&CK mitigations that cover these techniques

Privileged Account Management Multi-factor Authentication Vulnerability Scanning Password Policies Network Segmentation Limit Access to Resource Over Network

Affected technologies (1)

Redhat — Build OF Keycloak

CWEs

CWE-347

References

Raw JSON (NVD)

Show

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