CVE-2026-41326 — kata-containers
Fix: kata-containers/kata-containers@1b9e49eCVE-2026-41326 is a CWE-61 vulnerability in github.com/kata-containers/kata-containers. A fix is available for github.com/kata-containers/kata-containers — see the affected versions and patch details below.
Kata Containers: CopyFile Policy Subversion via Symlinks
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-41326.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
Real-World Exposure
github.com/kata-containers/kata-containersReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
Description
Kata Containers is an open source project focusing on a standard implementation of lightweight Virtual Machines (VMs) that perform like containers. From v3.4.0 to v3.28.0, an oversight in the CopyFile policy (and perhaps the CopyFile handler) allows untrusted hosts to write to arbitrary locations inside the guest workload image. This can be used to overwrite binaries inside the guest and exfiltrate data from containers; even those running inside CVMs. This vulnerability is fixed in v3.29.0.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/kata-containers/kata-containers | all versions | 0.0.0-20260422180503-1b9e49eb2763go get github.com/kata-containers/kata-containers@v0.0.0-20260422180503-1b9e49eb2763 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/kata-containers/kata-containers, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update github.com/kata-containers/kata-containers to 0.0.0-20260422180503-1b9e49eb2763 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-41326 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2026-41326 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2026-41326. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
This flaw in the CopyFile policy of Kata Containers allows untrusted hosts to write to arbitrary locations within a guest workload image. This could lead to the overwriting of binaries inside the guest and the exfiltration of data from containers, including those running within Confidential Virtual Machines (CVMs).
| Product | Fixed in | Advisory |
|---|---|---|
| Red Hat OpenShift Container Platform 4.19 | rhcos-4.19.9.6.202606100451-0 | RHSA-2026:25200 |
Frequently Asked Questions
Is CVE-2026-41326 in your dependencies?
O3 Security finds CVE-2026-41326 across Go dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.