Importing a crafted backup leads to project restriction bypass
Published Apr 9, 2026
9.1
CRITICALCVSS 3.1
EPSS 0.68%
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.
Affected products
-
- Version 4.12.0StatusaffectedConstraints<5.0.7
- Version 5.1.0StatusaffectedConstraints<5.21.5
- Version 6.0.0StatusaffectedConstraints<6.8.0
- Version
No data.
No Red Hat product state for this CVE.
github.com/canonical/lxd
Go
Introduced 0.0.0-20210305023314-538ac3df036e Fixed not fixed
| Ecosystem | Package | Introduced | Fixed |
|---|---|---|---|
| Go | github.com/canonical/lxd | 0.0.0-20210305023314-538ac3df036e | not fixed |
Remediation
No remediation recorded yet.
Metrics
No CVSS v4.0 score for this CVE.
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
No CVSS v3.0 score for this CVE.
No CVSS v2.0 score for this CVE.
This CVE is not in the KEV list.
CISA SSVC (Vulnrichment)
Stakeholder-Specific Vulnerability Categorization from CISA ADP.
Exploitation
PoCAutomatable
NoTechnical Impact
TotalDecision
n/aAssessed Apr 9, 2026 · SSVC 2.0.3
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 1, 2026.
Score over time
Apr–Oct 2026- EPSS v4
- EPSS v5
Percentile over time
- EPSS v4
- EPSS v5
Table of values (3 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 0.68% (0.00675) | 50.42th | v5 (v2026.06.15) |
| Jun 15, 2026 | 0.42% (0.00424) | 33.69th | v5 (v2026.06.15) |
| Apr 9, 2026 | 0.04% (0.00044) | 13.52th | v4 (v2025.03.14) |
References (4)
- https://github.com/advisories/GHSA-q96j-3fmm-7fv4 Advisory
- https://github.com/canonical/lxd/pull/17921 patchissue-trackingIssue Tracking
- https://github.com/canonical/lxd/security/advisories/GHSA-q96j-3fmm-7fv4 exploitvdb-entryvendor-advisoryThird Party Advisory
- https://nvd.nist.gov/vuln/detail/CVE-2026-34178
| Link | Providers | Tags |
|---|---|---|
| https://github.com/advisories/GHSA-q96j-3fmm-7fv4 | Advisory | |
| https://github.com/canonical/lxd/pull/17921 | patchissue-trackingIssue Tracking | |
| https://github.com/canonical/lxd/security/advisories/GHSA-q96j-3fmm-7fv4 | exploitvdb-entryvendor-advisoryThird Party Advisory | |
| https://nvd.nist.gov/vuln/detail/CVE-2026-34178 |
Change history (0)
No recorded changes yet.