Improper access control in Grafana - CVE-2026-33376
Published: May 18, 2026
Vulnerability identifier: #VU131637
CSH Severity: Medium
CVSS v4: 9.1 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-33376
CWE-ID: CWE-284
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to bypass IP-based access restrictions for the Auth Proxy feature.
The vulnerability exists due to improper access control in the Auth Proxy IPv6 allow-list handling when evaluating IPv6 addresses without an explicitly specified mask. A remote attacker can use an IPv6 address that matches the unintended default /32 range to bypass IP-based access restrictions for the Auth Proxy feature.
Only the Auth Proxy feature is affected; other authentication methods such as Okta, SAML, and LDAP are unaffected.
Affected software
Grafana
Red Hat Enterprise Linux for x86_64
Red Hat Enterprise Linux for IBM z Systems
Red Hat Enterprise Linux for Power, little endian
Red Hat Enterprise Linux for ARM 64
grafana (Red Hat package)
Red Hat Enterprise Linux for x86_64
Red Hat Enterprise Linux for IBM z Systems
Red Hat Enterprise Linux for Power, little endian
Red Hat Enterprise Linux for ARM 64
grafana (Red Hat package)
How to mitigate CVE-2026-33376
Install security update from vendor's website.
Grafana - addressed in versions 11.6.14+security-04, 12.2.8+security-04, 12.3.6+security-04, 12.4.3+security-02, 13.0.1+security-01
grafana (Red Hat package) - update to 10.2.6-28.el10_2.4
grafana (Red Hat package) - update to 10.2.6-28.el10_2.4