RHSA-2026:67518HighCVSS 8.8

Red Hat Security Advisory: grafana security update

Published
September 15, 2026
Last Modified
September 18, 2026

🔗 CVE IDs covered (11)

CVE-2026-33818 →CVE-2026-56853 →CVE-2026-56858 →CVE-2026-56859 →CVE-2026-56862 →CVE-2026-27137 →CVE-2026-33376 →CVE-2026-33377 →CVE-2026-33810 →CVE-2026-42127 →CVE-2026-56860 →

📋 Description

CVE-2026-27137 — crypto/x509: Incorrect enforcement of email constraints in crypto/x509 CVE-2026-33376 — grafana: Grafana Auth Proxy: Unauthorized access due to incorrect IPv6 allow-list default CVE-2026-33377 — grafana: Grafana: Privilege escalation via dashboard overwrite CVE-2026-33810 — crypto/x509: golang: Go crypto/x509: Certificate validation bypass due to incorrect DNS constraint application CVE-2026-33818 — encoding/asn1: golang: Go encoding/asn1: Denial of Service via excessive recursion in Unmarshal CVE-2026-42127 — grafana: Grafana: Denial of Service due to excessive memory allocation via large JSON payloads CVE-2026-56853 — net/http: golang: Go net/http: Unencrypted HTTP/2 connections vulnerable to Denial of Service CVE-2026-56858 — html/template: golang: Go html/template: Cross-Site Scripting via pathological input CVE-2026-56859 — encoding/xml: golang: Go: Denial of Service via XML decoding recursion depth issue CVE-2026-56860 — net/url: golang: golang net/url: Denial of Service from quadratic complexity in path resolution CVE-2026-56862 — crypto/tls: golang: Golang crypto/tls: Denial of Service via indefinite KeyUpdate messages

🎯 Affected products18

  • Red Hat Enterprise Linux AppStream EUS (v.9.6)
  • grafana-0:10.2.6-23.el9_6.aarch64 as a component of Red Hat Enterprise Linux AppStream EUS (v.9.6)
  • grafana-0:10.2.6-23.el9_6.ppc64le as a component of Red Hat Enterprise Linux AppStream EUS (v.9.6)
  • grafana-0:10.2.6-23.el9_6.s390x as a component of Red Hat Enterprise Linux AppStream EUS (v.9.6)
  • grafana-0:10.2.6-23.el9_6.src as a component of Red Hat Enterprise Linux AppStream EUS (v.9.6)
  • grafana-0:10.2.6-23.el9_6.x86_64 as a component of Red Hat Enterprise Linux AppStream EUS (v.9.6)
  • grafana-debuginfo-0:10.2.6-23.el9_6.aarch64 as a component of Red Hat Enterprise Linux AppStream EUS (v.9.6)
  • grafana-debuginfo-0:10.2.6-23.el9_6.ppc64le as a component of Red Hat Enterprise Linux AppStream EUS (v.9.6)
  • grafana-debuginfo-0:10.2.6-23.el9_6.s390x as a component of Red Hat Enterprise Linux AppStream EUS (v.9.6)
  • grafana-debuginfo-0:10.2.6-23.el9_6.x86_64 as a component of Red Hat Enterprise Linux AppStream EUS (v.9.6)
  • grafana-debugsource-0:10.2.6-23.el9_6.aarch64 as a component of Red Hat Enterprise Linux AppStream EUS (v.9.6)
  • grafana-debugsource-0:10.2.6-23.el9_6.ppc64le as a component of Red Hat Enterprise Linux AppStream EUS (v.9.6)
  • grafana-debugsource-0:10.2.6-23.el9_6.s390x as a component of Red Hat Enterprise Linux AppStream EUS (v.9.6)
  • grafana-debugsource-0:10.2.6-23.el9_6.x86_64 as a component of Red Hat Enterprise Linux AppStream EUS (v.9.6)
  • grafana-selinux-0:10.2.6-23.el9_6.aarch64 as a component of Red Hat Enterprise Linux AppStream EUS (v.9.6)
  • grafana-selinux-0:10.2.6-23.el9_6.ppc64le as a component of Red Hat Enterprise Linux AppStream EUS (v.9.6)
  • grafana-selinux-0:10.2.6-23.el9_6.s390x as a component of Red Hat Enterprise Linux AppStream EUS (v.9.6)
  • grafana-selinux-0:10.2.6-23.el9_6.x86_64 as a component of Red Hat Enterprise Linux AppStream EUS (v.9.6)

✅ Remediation

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 Workaround: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability. Workaround: To mitigate this issue, explicitly specify the intended IPv6 address mask—typically /128 for a single host—within the Grafana Auth Proxy allow-list configuration. This overrides the incorrect default /32 mask, ensuring that network access restrictions are applied strictly as intended. For RHEL: Update the whitelist directive under the [auth.proxy] section in /etc/grafana/grafana.ini. For example, if ::1 is the desired address, configure it explicitly as ::1/128. A restart of the Grafana service (systemctl restart grafana-server) is required for the changes to take effect. Workaround: Audit dashboard-level permissions to ensure that write access is granted only to users who should be able to modify each specific dashboard. Revoke per-dashboard write permissions from Editor users who do not strictly require them. Workaround: Restrict network access to the Grafana instance to only trusted clients and networks. This can be achieved by configuring firewall rules to limit inbound connections to the Grafana service port. If Grafana is exposed via a reverse proxy, ensure the proxy is configured to limit request body sizes to prevent large payloads from reaching Grafana. A service restart may be required for network configuration changes to take effect. Workaround: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.

🔗 References (14)