CVE-2026-63297
Cross-project instance copy bypasses target project restrictions via TOCTOU in config merge
An authorization bypass vulnerability in LXD due to a timing flaw during configuration merging allows an authenticated attacker to bypass target project restrictions during cross-project instance copies. When copying an instance to a target project, LXD performs restriction checks before configuration merging is complete, creating a time-of-check to time-of-use (TOCTOU) condition. An attacker can exploit this flaw to copy instances with disallowed high-privilege configurations into restricted projects, bypassing security controls.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
9.9
Cross-project instance copy bypasses target project restrictions via TOCTOU in config merge
An authorization bypass vulnerability in LXD due to a timing flaw during configuration merging allows an authenticated attacker to bypass target project restrictions during cross-project instance copies. When copying an instance to a target project, LXD performs restriction checks before configuration merging is complete, creating a time-of-check to time-of-use (TOCTOU) condition. An attacker can exploit this flaw to copy instances with disallowed high-privilege configurations into restricted projects, bypassing security controls.
- Record
CVE-2026-63297- CVSS 3.1
- 9.9 Critical
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H - Weakness
- CWE-367, CWE-863
- Updated
- 2026-11-02
EUVDEUVD-2026-57513
9.9
An authorization bypass vulnerability in LXD due to a timing flaw during configuration merging allows an authenticated attacker to bypass target project restrictions during cross-project instance copies. When copying an instance to a target project, LXD performs restriction checks before configuration merging is complete, creating a time-of-check to time-of-use (TOCTOU) condition. An attacker can exploit this flaw to copy instances with disallowed high-privilege configurations into restricted projects, bypassing security controls.
- Record
EUVD-2026-57513- CVSS 3.1
- 9.9 Critical
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H - Updated
- 2026-11-02
NVD
9.9
An authorization bypass vulnerability in LXD due to a timing flaw during configuration merging allows an authenticated attacker to bypass target project restrictions during cross-project instance copies. When copying an instance to a target project, LXD performs restriction checks before configuration merging is complete, creating a time-of-check to time-of-use (TOCTOU) condition. An attacker can exploit this flaw to copy instances with disallowed high-privilege configurations into restricted projects, bypassing security controls.
- Record
CVE-2026-63297- CVSS 3.1
- 9.9 Critical
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H - Weakness
- CWE-367, CWE-863
- Updated
- 2026-11-02
OSV
9.9
Cross-project instance copy bypasses target project restrictions via TOCTOU in config merge
An authorization bypass vulnerability in LXD due to a timing flaw during configuration merging allows an authenticated attacker to bypass target project restrictions during cross-project instance copies. When copying an instance to a target project, LXD performs restriction checks before configuration merging is complete, creating a time-of-check to time-of-use (TOCTOU) condition. An attacker can exploit this flaw to copy instances with disallowed high-privilege configurations into restricted projects, bypassing security controls.
- Record
CVE-2026-63297- CVSS 3.1
- 9.9 Critical
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H - Weakness
- CWE-367, CWE-863
- Updated
- 2026-11-02
OSVDEBIAN-CVE-2026-63297
9.9
An authorization bypass vulnerability in LXD due to a timing flaw during configuration merging allows an authenticated attacker to bypass target project restrictions during cross-project instance copies. When copying an instance to a target project, LXD performs restriction checks before configuration merging is complete, creating a time-of-check to time-of-use (TOCTOU) condition. An attacker can exploit this flaw to copy instances with disallowed high-privilege configurations into restricted projects, bypassing security controls.
- Record
DEBIAN-CVE-2026-63297- CVSS 3.1
- 9.9 Critical
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H - Updated
- 2026-11-02
OSVUBUNTU-CVE-2026-63297
9.9
An authorization bypass vulnerability in LXD due to a timing flaw during configuration merging allows an authenticated attacker to bypass target project restrictions during cross-project instance copies. When copying an instance to a target project, LXD performs restriction checks before configuration merging is complete, creating a time-of-check to time-of-use (TOCTOU) condition. An attacker can exploit this flaw to copy instances with disallowed high-privilege configurations into restricted projects, bypassing security controls.
- Record
UBUNTU-CVE-2026-63297- CVSS 3.1
- 9.9 Critical
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H - Updated
- 2026-11-02
OSVopenSUSE-SU-2026:21788-1 No score
Security update for lxd
This update for lxd fixes the following issues:
Changes in lxd:
-
update to 5.21.6:
- bsc#1274937, CVE-2026-63293, bsc#1274936, CVE-2026-62420, bsc#1274954, CVE-2026-63295, bsc#1274963, CVE-2026-63297, bsc#1274961, CVE-2026-63296, bsc#1275085, CVE-2026-63299, bsc#1275084, CVE-2026-63298, bsc#1275090, CVE-2026-66898
- https://canonical.com/lxd/docs/latest/reference/release- notes/5.21/release-notes-5.21.6/
- https://canonical.com/lxd/docs/latest/reference/release- notes/5.21/release-notes-5.21.5/
- https://discourse.ubuntu.com/t/lxd-5-21-4-lts-has-been- released/66602
- https://discourse.ubuntu.com/t/lxd-5-21-3-lts-has-been- released/53768
- https://discourse.ubuntu.com/t/lxd-5-21-2-has-been- released/46443
-
Migrate to single LXD/Incus OVMF handling (lxd-ovmf-setup):
- Allow aarch64 arch_vm_support
- Remove OVMF symlinks
- Require the new lxd-ovmf-setup packages
- Record
openSUSE-SU-2026:21788-1- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
lxdDebian:12 |
All versions, plus listed versions 5.0.2+git20231211.1364ae4-15.0.2+git20231211.1364ae4-25.0.2+git20231211.1364ae4-35.0.2+git20231211.1364ae4-45.0.2+git20231211.1364ae4-5 Show 12 moreShow less5.0.2+git20231211.1364ae4-65.0.2+git20231211.1364ae4-75.0.2+git20231211.1364ae4-85.0.2+git20231211.1364ae4-95.0.2-55.0.2-5+deb12u15.0.2-5+deb12u25.0.2-5+deb12u35.0.2-5+deb12u45.0.2-5+deb12u55.0.2-5+deb12u65.0.2-6 |
None known |
lxdDebian:13 |
All versions, plus listed versions 5.0.2+git20231211.1364ae4-95.0.2+git20231211.1364ae4-9+deb13u15.0.2+git20231211.1364ae4-9+deb13u25.0.2+git20231211.1364ae4-9+deb13u35.0.2+git20231211.1364ae4-9+deb13u45.0.2+git20231211.1364ae4-9+deb13u55.0.2+git20231211.1364ae4-9+deb13u65.0.2+git20231211.1364ae4-9+deb13u7 |
None known |
lxdUbuntu:Pro:16.04:LTS |
All versions, plus listed versions 0.20-0ubuntu40.21-0ubuntu30.21-0ubuntu50.22-0ubuntu10.22-0ubuntu2 Show 45 moreShow less0.23-0ubuntu10.23-0ubuntu20.23-0ubuntu30.24-0ubuntu20.24-0ubuntu30.24-0ubuntu40.25-0ubuntu10.26-0ubuntu20.26-0ubuntu30.27-0ubuntu10.27-0ubuntu22.0.0~beta1-0ubuntu32.0.0~beta1-0ubuntu42.0.0~beta2-0ubuntu12.0.0~beta2-0ubuntu22.0.0~beta3-0ubuntu12.0.0~beta3-0ubuntu22.0.0~beta3-0ubuntu32.0.0~beta3-0ubuntu42.0.0~beta4-0ubuntu12.0.0~beta4-0ubuntu22.0.0~beta4-0ubuntu32.0.0~beta4-0ubuntu42.0.0~beta4-0ubuntu52.0.0~beta4-0ubuntu62.0.0~beta4-0ubuntu72.0.0~rc1-0ubuntu12.0.0~rc1-0ubuntu22.0.0~rc1-0ubuntu32.0.0~rc2-0ubuntu22.0.0~rc2-0ubuntu32.0.0~rc3-0ubuntu12.0.0~rc3-0ubuntu22.0.0~rc3-0ubuntu32.0.0~rc3-0ubuntu42.0.0~rc4-0ubuntu12.0.0~rc5-0ubuntu12.0.0~rc6-0ubuntu12.0.0~rc6-0ubuntu22.0.0~rc7-0ubuntu12.0.0~rc7-0ubuntu22.0.0~rc8-0ubuntu12.0.0~rc8-0ubuntu22.0.0~rc8-0ubuntu32.0.0~rc8-0ubuntu5 |
None known |
lxdUbuntu:Pro:18.04:LTS |
All versions, plus listed versions 2.18-0ubuntu62.19-0ubuntu12.20-0ubuntu32.20-0ubuntu42.21-0ubuntu1 Show 18 moreShow less2.21-0ubuntu22.21-0ubuntu32.21-0ubuntu43.0.0~beta2-0ubuntu33.0.0~beta3-0ubuntu33.0.0~beta5-0ubuntu23.0.0~beta7-0ubuntu13.0.0-0ubuntu13.0.0-0ubuntu23.0.0-0ubuntu33.0.0-0ubuntu43.0.1-0ubuntu1~18.04.13.0.2-0ubuntu1~18.04.13.0.3-0ubuntu1~18.04.13.0.3-0ubuntu1~18.04.23.0.3-0ubuntu1~18.04.2+esm13.0.3-0ubuntu1~18.04.2+esm23.0.3-0ubuntu1~18.04.2+esm3 |
None known |
lxdUbuntu:20.04:LTS |
All versions, plus listed versions 1:0.71:0.81:0.91:0.10 |
None known |
lxdopenSUSE:Leap 16.0 |
before 5.21.6-bp160.1.1 | 5.21.6-bp160.1.1 |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-63297 is a critical vulnerability (CVSS 9.9) in Canonical Lxd, published August 12, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.34%, the 28th percentile. Fixed in lxd 5.21.6-bp160.1.1.
References
github.com/canonical/lxd/security/advisories/GHSA-v989-qw7w-xvg4
github.com/CVEProject/cvelistV5/tree/main/cves/2026/63xxx/CVE-2026-63297.json
nvd.nist.gov/vuln/detail/CVE-2026-63297
github.com/canonical/lxd
security-tracker.debian.org/tracker/CVE-2026-63297
ubuntu.com/security/CVE-2026-63297
Show 19 moreShow less
cve.org/CVERecord?id=CVE-2026-63297
bugzilla.suse.com/1223794
bugzilla.suse.com/1274936
bugzilla.suse.com/1274937
bugzilla.suse.com/1274954
bugzilla.suse.com/1274961
bugzilla.suse.com/1274963
bugzilla.suse.com/1275084
bugzilla.suse.com/1275085
bugzilla.suse.com/1275090
suse.com/security/cve/CVE-2023-46565
suse.com/security/cve/CVE-2026-62420
suse.com/security/cve/CVE-2026-63293
suse.com/security/cve/CVE-2026-63295
suse.com/security/cve/CVE-2026-63296
suse.com/security/cve/CVE-2026-63297
suse.com/security/cve/CVE-2026-63298
suse.com/security/cve/CVE-2026-63299
suse.com/security/cve/CVE-2026-66898
Left out here: 26 versions. The JSON record has them.