How severe is CVE-2026-34178?

CVE-2026-34178 has a CVSS 3.x base score of 9.1, rated critical severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2026-34178 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (51st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-34178?

CVE-2026-34178 affects Canonical Lxd. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-34178?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

Does CVE-2026-34178 have an EU (EUVD) identifier?

Yes. CVE-2026-34178 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-20874.

When was CVE-2026-34178 published?

CVE-2026-34178 was published on 2026-04-09 and last updated on 2026-06-17.

CVE-2026-34178

CVE-2026-34178 is a critical-severity vulnerability in Canonical Lxd with a CVSS 3.x base score of 9.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-20.

Key facts

Severity: Critical (CVSS 3.x base score 9.1)
EPSS exploit prediction: 1% (51st percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-20874
Weakness: CWE-20
Affected product: Canonical Lxd
Published: 2026-04-09
Last modified: 2026-06-17

Description

In Canonical LXD before 6.8, the backup import path validates project restrictions against backup/index.yaml in the supplied tar archive but creates the instance from backup/container/backup.yaml, a separate file in the same archive that is never checked against project restrictions. An authenticated remote attacker with instance-creation permission in a restricted project can craft a backup archive where backup.yaml carries restricted settings such as security.privileged=true or raw.lxc directives, bypassing all project restriction enforcement and allowing full host compromise.

Frequently asked questions

What is CVE-2026-34178?: In Canonical LXD before 6.8, the backup import path validates project restrictions against backup/index.yaml in the supplied tar archive but creates the instance from backup/container/backup.yaml, a separate file in the same archive that is never checked against project restrictions. An authenticated remote attacker with instance-creation permission in a restricted project can craft a backup archive where backup.yaml carries restricted settings such as security.privileged=true or raw.lxc directives, bypassing all project restriction enforcement and allowing full host compromise.
How severe is CVE-2026-34178?: CVE-2026-34178 has a CVSS 3.x base score of 9.1, rated critical severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-34178 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (51st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-34178?: CVE-2026-34178 affects Canonical Lxd. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-34178?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
Does CVE-2026-34178 have an EU (EUVD) identifier?: Yes. CVE-2026-34178 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-20874.
When was CVE-2026-34178 published?: CVE-2026-34178 was published on 2026-04-09 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:canonical:lxd:*:*:*:*:*:*:*:*

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