CVE-2026-9099 | Keycloak: group-admin escalation to realm-admin

A flaw was found in Keycloak. A missing authorization check in the GroupResource.addChild() endpoint within the Admin REST API allows an authenticated user with limited administrative privileges to reparent any existing group. When Fine-Grained Admin Permissions v2 (FGAPv2) is enabled, an attacker with management rights over a single low-privilege group can reparent a highly privileged group (such as one possessing the realm-admin role) under their managed group. Because group permissions follow a hierarchical structure, this action unauthorizedly grants the attacker management and password-reset capabilities over the members of the targeted privileged group. An attacker can exploit this to reset an administrator's password, compromise the account, and achieve a full realm takeover, leading to a complete compromise of confidentiality, integrity, and availability.

Published: 2026-06-25 Last update: 2026-07-01 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-9099 is rated Low Risk (37.2/100): CVSS High severity, with low exploitation likelihood (EPSS 0.27%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-9099

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-26 — 0.27% —

Full EPSS history (1 record total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-9099

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.7 3.1 HIGH
CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:H)
They need powerful rights—admin, root, or similar—before this pays off.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N)
Service keeps running; no real outage angle.
 1.3 5.8 [email protected]
7.7 3.1 HIGH
CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:H)
They need powerful rights—admin, root, or similar—before this pays off.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N)
Service keeps running; no real outage angle.
 1.3 5.8 0b0ca135-0b70-47e7-9f44-1890c2a1c46c

Weakness enumeration for CVE-2026-9099

GitHub Security Advisory for CVE-2026-9099

GHSA-rmcj-82cr-27rx · Severity: high — A flaw was found in Keycloak. A missing authorization check in the GroupResource.addChild()...

OS Trackers for CVE-2026-9099

vendor priority summary link
redhat high — https://access.redhat.com/security/cve/CVE-2026-9099

Affected software / configurations for CVE-2026-9099

Vendor Product Version Raw CPE
redhat build_of_keycloak >= 26.4, < 26.4.13 cpe:2.3:a:redhat:build_of_keycloak:*:*:*:*:*:*:*:*
redhat build_of_keycloak >= 26.6, < 26.6.4 cpe:2.3:a:redhat:build_of_keycloak:*:*:*:*:*:*:*:*

References for CVE-2026-9099

cvelogic Threat Intelligence