CVE-2026-71566
FakeFish + KubeVirt flaw lets any cluster user control other users' VMs
Is CVE-2026-71566 being exploited?
Not confirmed. CVE-2026-71566 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.21% probability of exploitation in the next 30 days.
How severe is CVE-2026-71566?
CVE-2026-71566 is rated Critical with a CVSS score of 9.3. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-71566?
Yes. A fix has been recorded for CVE-2026-71566. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-71566 affect?
CVE-2026-71566 affects FakeFish, KubeVirt, Kubernetes clusters running KubeVirt, VMs managed by KubeVirt. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-71566?
Restrict RBAC, remove untrusted KUBECONFIG mounts, block/remove FakeFish, apply vendor patch when released
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Any cluster user can power on/off VMs and mount arbitrary CD images of VMs created by another user, enabling VM tampering, data access, and persistence.
Immediate action required
- affected<= 28f9a6b
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.