CVE-2026-49823 Fission: Cross-namespace Package read via unvalidated PackageRef in Function admission webhook
Attackers can read packages from other namespaces due to missing validation in the admission webhook, exposing sensitive data.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-49823?
CVE-2026-49823 is a high-severity missing authorization vulnerability in fission, published on 10 Jun 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
Fission is an open-source, Kubernetes-native serverless framework that simplifies the deployment of functions and applications on Kubernetes. Prior to version 1.24.0, a Fission Function spec carries three reference types — Secret, ConfigMap, and Package. The first two were namespace-validated by the admission webhook; PackageRef.Namespace was not. This issue has been patched in version 1.24.0.
Which versions are affected by CVE-2026-49823?
3 open source packages ship an affected version, including github.com/fission/fission.
| Package | Affected | Fixed in |
|---|---|---|
github.com/fission/fission Go | All versions | 1.24.0 |
github.com/fission/fission Go | All versions | 1.24.0 |
github.com/fission/fission Go | All versions | 1.24.0 |
How do I fix CVE-2026-49823?
Upgrade github.com/fission/fission to 1.24.0 or later.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2026-49823 being exploited?
There is no known exploitation of CVE-2026-49823 in the wild and no public exploit code.
Sources
Also known as GHSA-3r8v-2xmj-5c39, GO-2026-5846.