# CVE-2026-18107: Criu: criu: container escape via rseq critical section hijack during checkpoint/restore

> A malicious container process can hijack CRIU checkpointing to spoof credentials, potentially gaining elevated capabilities upon restore.

- **Severity:** High 7.8 (`CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 28 Jul 2026
- **Updated:** 1 Sep 2026
- **Also known as:** AZL-94154, DEBIAN-CVE-2026-18107, GHSA-hm7v-8wcp-3gjm, UBUNTU-CVE-2026-18107

## What is CVE-2026-18107?

CVE-2026-18107 is a high-severity vulnerability in Red Hat Enterprise Linux 10, published on 28 Jul 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### 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.

Weakness: CWE-269 (Improper Privilege Management)

## Which versions are affected by CVE-2026-18107?


## How do I fix CVE-2026-18107?

Apply the vendor's patch.

## Is CVE-2026-18107 being exploited?

There is no known exploitation of CVE-2026-18107 in the wild and no public exploit code.

Public exploit code:

- Universal container escape exploit targeting the CRIU container checkpoint/restore system - CVE-2026-18107 (github_poc): https://github.com/robalb/criu-exploit

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-18107 and fix it if it is affected.

What it is: CVE-2026-18107 is a high-severity vulnerability in Red Hat Enterprise Linux 10, published on 28 Jul 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-18107 in the wild and no public exploit code.

Affected product: Red Hat Enterprise Linux 10. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-18107/ (Markdown: https://insights.sbomify.com/CVE-2026-18107/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-18107
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-18107
- OSV: https://osv.dev/vulnerability/CVE-2026-18107

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-18107/
Summaries are generated and may contain mistakes; the official description above is the record.