CVE-2026-87799 Details
Description
Improper link resolution in the migration receive path in Canonical LXD versions 4.0 and later (fixed in 4.0.14, 5.0.10, 5.21.8 and 6.10) on Linux allows an authenticated client that can create instances or custom storage volumes in a project, or a malicious migration source server, to write attacker-controlled files to arbitrary paths on the target host as root, leading to full host compromise. The attacker does this with a crafted rsync or btrfs send stream that plants a symlink in the transferred volume, such as rootfs or root.img, and then writes through it.
A vulnerability in Canonical LXD versions 4.0 and later, excluding 4.0.14, 5.0.10, 5.21.8 and 6.10, allows an authenticated client to write files to arbitrary paths on the host as root. This issue arises from improper link resolution in the migration receive path, where a malicious migration source can exploit the transfer process to plant symlinks that redirect to sensitive areas of the filesystem. The vulnerability could lead to a full host compromise.
Users are advised to update to LXD versions 4.0.14, 5.0.10, 5.21.8 or 6.10. Additionally, it is recommended to only allow trusted clients to create instances and custom volumes, and to migrate from trusted servers.
Metrics
CVSS 4.0 Severity and Vector Strings:
VolerionCVSS 3.x Severity and Vector Strings:
No data available for CVSS Version 2.0 on this CVE.
Volerion
Assessed Sep 28, 2026CISA-ADP
Assessed Sep 28, 2026References to Advisories, Solutions, and Tools
By selecting these links, you will be leaving this site. These are references gathered from the official CVE record and are not endorsed by Volerion.
| URL | Source(s) | Tag(s) |
|---|---|---|
| https://github.com/canonical/lxd/security/advisories/GHSA-fmc3-3cpq-6whr | [email protected] | AdvisoryRemedyVendor |
Weakness Enumeration
| CWE-ID | CWE Name | Source |
|---|---|---|
| CWE-59 | Improper Link Resolution Before File Access ('Link Following') | [email protected] |
Affected Products
| Product | Versions |
|---|---|
| Canonical LXD | >= 4.0 |
CPE
Remediation
| |
Change History
3 change records found show changes
| Date | Action | Recorded By |
|---|---|---|
| Sep 29, 2026 | CVE Modified | CISA-ADP |
| Sep 28, 2026 | CVE Modified | CISA-ADP |
| Sep 28, 2026 | New CVE Received | [email protected] |