Improper link resolution in the migration receive path in Canonical LXD versions 4.0 and later (fixed in 4.0.14…
Summary
Vulnerability reported (CVE-2026-87799). Successful exploitation can lead to full system takeover. Mitigation: upgrade to 4.0.14 or later.
Original description
The description as published by the source.
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.
Source: NIST National Vulnerability Database NVD
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-87799 has been found.
Successful exploitation can lead to full system takeover. CVSS score: 9.9/10.
What to do: upgrade the affected software to 4.0.14 or later.
If unsure, ask your IT team or search "CVE-2026-87799" on the vendor's site.
CVE-2026-87799 — CWE-59 / CVSS v3 9.9
Attack vector: remote (network-reachable) / no user interaction
Patched: 4.0.14 — apply immediately
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (CWE-59) has been reported.
Check the vendor advisory for the affected versions.
Severity: Critical (CVSS 9.9/10). Successful exploitation can lead to full system takeover.
Update to 4.0.14.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Audit SBOM/dependencies to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
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1Identify exposure identify
Audit SBOM/dependencies for affected components.資産台帳・SBOM・依存マニフェストで影響コンポーネントを特定する。
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2Apply patch patch
Upgrade to 4.0.14ステージング環境で 4.0.14 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
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3Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Fix status by distribution
Fixed packages published by each distribution for this CVE
- Ubuntu UBUNTU-CVE-2026-87799 lxd