Arbitrary file write on LXD host via symlink in migration stream (Canonical LXD)

CVE-2026-87799
CRITICAL 9.9

At a glance

Source
NVD
EPSS
EPSS 0.41 % · percentile 35 ()
State
PUBLISHED
Published
Updated
Assigner
canonical
NVD status
Deferred

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.

Weaknesses (CWE)

  • CWE-59 — Improper Link Resolution Before File Access

References

Scores

VersionScoreVectorScored by
CVSS 3.1CRITICAL 9.9CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:Hcanonical
CVSS 3.1CRITICAL 9.9CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:HNVD · security@ubuntu.com (Secondary)

European references

Affected products

ProductVersions
Canonical · LXDaffected 4.0.0 < 4.0.14 ; affected 5.0.0 < 5.0.10 ; affected 5.21.0 < 5.21.8 ; affected 6.0 < 6.10

Sources

SourceLicence
CVE List (CVEProject cvelistV5)CVE Program Terms of Use
EPSS (FIRST.org)FIRST — attribution requested
ENISA EUVDENISA — reproduction authorised, source acknowledged
NVD (NIST) via fkie-cad/nvd-json-data-feedsPublic domain — this product uses data from the NVD API but is not endorsed or certified by the NVD