CVE-2026-66898
LXD backup path traversal allows file overwrite/read outside restore directory
Is CVE-2026-66898 being exploited?
Not confirmed. CVE-2026-66898 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 0.43% probability of exploitation in the next 30 days.
How severe is CVE-2026-66898?
CVE-2026-66898 is rated Critical with a CVSS score of 9.9. 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-2026-66898?
Yes. A fix has been recorded for CVE-2026-66898. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-66898 affect?
CVE-2026-66898 affects LXD (backup import/restore functionality), Hosts running LXD, Containers and storage volumes managed by LXD. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-66898?
Do not import untrusted backups; restrict restore privileges; apply vendor patch when released.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Crafted backup archive during import/restore can read or overwrite files outside the restore dir, risking host/container compromise and data tampering.
Immediate action required
- affected>= 4.0.0 and < 4.0.12
- affected>= 5.0.0 and < 5.0.4
- affected>= 5.21.0 and < 5.21.2
- affected>= 6.0 and < 6.1
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.