Vulnerability · Published Jul 28, 2026 · Assigned by redhat
CVE-2026-18107Criu: criu: container escape via rseq critical section hijack during checkpoint/restore
High 7.8
In plain English
A high-severity privilege mismanagement in Red Hat Enterprise Linux 10 from Red Hat. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 5% of all known vulnerabilities). Ready-made attack tooling exists: public proof-of-concept code. Fixed versions are available - upgrade the affected package.
Official description
A flaw was found in CRIU's handling of restartable sequences (rseq) during checkpoint/restore. A malicious process inside a container can register an rseq critical section that hijacks CRIU's parasite code injection during checkpoint, allowing it to spoof the process credentials saved in the checkpoint image. On restore, the container process gains elevated capabilities and zeroed UIDs/GIDs. The practical impact on Red Hat products is limited by several factors: checkpoint/restore requires root privileges (podman) or cluster-admin RBAC (OpenShift) to trigger and cannot be initiated from within the container itself; on OpenShift prior to 4.17 the feature required explicit opt-in, and on 4.17+ the kubelet checkpoint API RBAC is not configured by default; OpenShift enforces user namespaces by default for regular workloads (hostUsers is gated behind admin-only SCCs), which makes the spoofed capabilities namespace-scoped and ineffective for privilege escalation; SELinux type enforcement (container_t) blocks privilege transitions independently of capabilities; seccomp filters persist through checkpoint/restore and cannot be corrupted via the parasite; and kernel mount namespace ownership checks on RHEL 9/10 kernels prevent mount-based container escape even with spoofed capabilities.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | criu | no fix listed | DEBIAN-CVE-2026-18107 |
| Debian:13 | criu | no fix listed | DEBIAN-CVE-2026-18107 |
| Debian:14 | criu | 4.2-5 | DEBIAN-CVE-2026-18107 |
| Ubuntu:22.04:LTS | criu | no fix listed | UBUNTU-CVE-2026-18107 |
| Ubuntu:26.04:LTS | criu | no fix listed | UBUNTU-CVE-2026-18107 |
| Ubuntu:26.10 | criu | no fix listed | UBUNTU-CVE-2026-18107 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Red Hat | Red Hat Enterprise Linux 10 | see references |
| Red Hat | Red Hat Enterprise Linux 7 | see references |
| Red Hat | Red Hat Enterprise Linux 8 | see references |
| Red Hat | Red Hat Enterprise Linux 8 | see references |
| Red Hat | Red Hat Enterprise Linux 9 | see references |
| Red Hat | Red Hat OpenShift Container Platform 4 | see references |
| Red Hat | Red Hat OpenShift Container Platform 4 | see references |
| Red Hat | Red Hat OpenShift Container Platform 4 | see references |
| Red Hat | Red Hat OpenShift Container Platform 5 | see references |
Weakness: CWE-269 · Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H
References
- https://access.redhat.com/security/cve/CVE-2026-18107 vdb-entry, x_refsource_REDHAT
- RHBZ#2508140 issue-tracking, x_refsource_REDHAT
- https://github.com/checkpoint-restore/criu/pull/3097