Which versions of Kata Containers are affected by CVE-2026-41326?

Kata Containers versions 3.4.0 through 3.28.0 contain an arbitrary file write vulnerability that allows untrusted hosts to overwrite guest binaries and exfiltrate data, creating a critical breach of…. A patch is available.

Is there a public PoC exploit available for CVE-2026-41326?

Yes, a public proof-of-concept exploit is available for CVE-2026-41326. Prioritise patching immediately. EPSS: 0.0%.

How to fix or mitigate CVE-2026-41326?

Within 24 hours: Identify all systems running Kata Containers versions 3.4.0-3.28.0 using inventory tools; document affected production and development environments. Within 7 days: Upgrade to Kata Containers v3.29.0 or later on non-production systems; validate functionality in staging. Within 30 days: Complete upgrade to v3.29.0+ on all production systems; implement host access controls to restrict file write operations to guest images during the transition period.

Kata Containers CVE-2026-41326

Q: What is the CVSS score of CVE-2026-41326?

CVE-2026-41326 has a CVSS 4.0 base score of 8.2 (High). CVSS vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:H/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X. EPSS exploitation probability: 0.0%.

EUVD-2026-25611 HIGH

UNIX Symbolic Link (Symlink) Following (CWE-61)

2026-04-24 GitHub_M

GHSA-q49m-57vm-c8cc

Information Disclosure Kata Containers

8.2

CVSS 4.0 · Vendor: GitHub_M

Severity by source

Vendor (GitHub_M) PRIMARY

8.2 HIGH

CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:H/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Red Hat

8.8 HIGH

qualitative

Primary rating from Vendor (GitHub_M).

CVSS VectorVendor: GitHub_M

CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:H/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Attack Vector

Local

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Lifecycle Timeline

Patch released

May 04, 2026 - 17:16 nvd

Patch available

Re-analysis Queued

Apr 27, 2026 - 14:22 vuln.today

cvss_changed

Patch available

Apr 24, 2026 - 21:02 EUVD

Analysis Generated

Apr 24, 2026 - 19:45 vuln.today

CVSS changed

Apr 24, 2026 - 19:22 NVD

8.2 (HIGH)

EUVD ID Assigned

Apr 24, 2026 - 19:15 euvd

EUVD-2026-25611

Analysis Generated

Apr 24, 2026 - 19:15 vuln.today

CVE Published

Apr 24, 2026 - 18:46 nvd

HIGH 8.2

DescriptionCVE.org

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.

AnalysisAI

Arbitrary file write in Kata Containers v3.4.0 to v3.28.0 allows untrusted hosts to overwrite binaries and exfiltrate data from guest workloads, including those in confidential VMs (CVMs). The vulnerability stems from inadequate validation in the CopyFile policy, permitting host-initiated writes to arbitrary paths inside guest images. This enables binary replacement for code execution or data theft across the trust boundary. Patched in v3.29.0. EPSS data not available; no active exploitation confirmed at time of analysis.

Technical ContextAI

Kata Containers implements container workloads as lightweight VMs to provide stronger isolation than traditional container runtimes. The architecture includes a guest kernel, guest agent, and host-side runtime that communicate via protocols like vsock or virtio-serial. The CopyFile mechanism allows the host runtime to transfer files into the guest filesystem. CWE-61 (UNIX Symbolic Link Following) indicates the vulnerability likely involves path traversal or symlink manipulation allowing writes outside intended directories. The CVSS 4.0 vector shows local attack vector (AV:L) with high integrity impact on both the vulnerable system (VI:H) and subsequent systems (SI:H changed to SC:H scope), reflecting cross-boundary compromise between host and isolated guest. In confidential computing deployments (CVMs), this breaks the fundamental trust model where the guest is protected from a potentially malicious host.

RemediationAI

Upgrade to Kata Containers version 3.29.0 or later, which contains the fix for the CopyFile policy validation. The vendor advisory at https://github.com/kata-containers/kata-containers/security/advisories/GHSA-q49m-57vm-c8cc provides complete upgrade guidance. No effective workarounds exist short of disabling the CopyFile functionality entirely, which would likely break core container lifecycle operations including image provisioning and volume mounting. For environments unable to upgrade immediately, compensating controls include restricting host access to trusted administrators only (reducing AV:L exposure), implementing file integrity monitoring inside guest workloads to detect unauthorized binary modifications, and avoiding deployment of sensitive workloads or confidential VMs on vulnerable versions. These controls do not eliminate the vulnerability but reduce attack surface and improve detection capabilities. Security teams should prioritize patching over workarounds given the trust boundary nature of this flaw.