CVE-2026-66793: Improper Input Validation
Source GCVE Database
Not known to be exploited · CVSS 8.8 High : patch Red Hat Advanced Cluster Management for Kubernetes 2.11 soon.
Data as of 26 Oct 2026, 17:16 UTC
- EPSS
- 0.8% chance of exploitation in 30 days – higher than 56% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 18 Aug 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Patches and advisories
- access.redhat.com/errata/RHSA-2026:60386 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:60387 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:60388 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:60389 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:60390 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:60391 (opens in a new tab)
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Red HatRed Hat Advanced Cluster Management for Kubernetes 2.11 | Affected– | Fixed in– |
| Red HatRed Hat Advanced Cluster Management for Kubernetes 2.13 | Affected– | Fixed in– |
| Red HatRed Hat Advanced Cluster Management for Kubernetes 2.14 | Affected– | Fixed in– |
| Red HatRed Hat Advanced Cluster Management for Kubernetes 2.15 | Affected– | Fixed in– |
| Red HatRed Hat Advanced Cluster Management for Kubernetes 2.16 | Affected– | Fixed in– |
| Red HatRed Hat Advanced Cluster Management for Kubernetes 2.17 | Affected– | Fixed in– |
Description
A flaw was found in the governance-policy-addon-controller component of Red Hat Advanced Cluster Management for Kubernetes. A user with permissions to annotate the namespaced ManagedClusterAddOn resource can override the governance-policy container image. This allows an attacker to run a controlled image with cluster-admin privileges on the managed cluster, leading to arbitrary code execution and privilege escalation.
References
- nvd.nist.gov/vuln/detail/CVE-2026-66793 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:60386 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:60387 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:60388 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:60389 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:60390 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:60391 (opens in a new tab)
- access.redhat.com/security/cve/CVE-2026-66793 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2507538 (opens in a new tab)