GHSA-hq4m-4948-64cc CVE-2023-34091 GO-2023-1819
Kyverno resource with a deletionTimestamp may allow policy circumvention
- Severity
- 6.5 / 10
- Medium · CVSS 3.1
- Exploit chance (EPSS)
- 0.50%
- Chance of exploitation in the next 30 days. Higher than 42.61% of scored vulnerabilities.
- Known exploited
- No
- Not in CISA's catalog
- Weakness
- CWE-285 Improper Authorization
- Fix
1.10.0- Upgrade github.com/kyverno/kyverno to this version or later
Description
Impact
In versions of Kyverno prior to 1.10.0, resources which have the deletionTimestamp field defined can bypass validate, generate, or mutate-existing policies, even in cases where the validationFailureAction field is set to Enforce.
This situation occurs as resources pending deletion were being consciously exempted by Kyverno, as a way to reduce processing load as policies are typically not applied to objects which are being deleted.
However, this could potentially result in allowing a malicious user to leverage the Kubernetes finalizers feature by setting a finalizer which causes the Kubernetes API server to set the deletionTimestamp and then not completing the delete operation as a way to explicitly to bypass a Kyverno policy.
Note that this is not applicable to Kubernetes Pods but, as an example, a Kubernetes Service resource can be manipulated using an indefinite finalizer to bypass policies.
Patches
This is resolved in Kyverno 1.10.0.
Workarounds
There is no known workaround.
References
Are there any links users can visit to find out more?
Affected versions
Go
| Package | Vulnerable | Fixed in |
|---|---|---|
| github.com/kyverno/kyverno | < 1.10.0 |
1.10.0 |
How to fix
Move to the fixed version or later with your package manager, update the lockfile, and run your tests. If the package only arrives through another dependency, upgrade that dependency first. If none of its releases pulls a fixed version yet, force the version with your package manager's override.
github.com/kyverno/kyverno Go → 1.10.0
- go
go get github.com/kyverno/kyverno@v1.10.0 && go mod tidy
Severity breakdown
CVSS 3.1 6.5
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- High
- Availability
- None
Weakness
CWE-285: Improper Authorization
The product does not perform or incorrectly performs an authorization check when an actor attempts to access a resource or perform an action.
How to prevent it
- Architecture and Design: Divide the product into anonymous, normal, privileged, and administrative areas. Reduce the attack surface by carefully mapping roles with data and functionality. Use role-based access control (RBAC) to enforce the roles at the appropriate boundaries. Note that this approach may not protect against horizontal authorization, i.e., it will not protect a user from attacking others with the same role.
- Architecture and Design: Ensure that you perform access control checks related to your business logic. These checks may be different than the access control checks that you apply to more generic resources such as files, connections, processes, memory, and database records. For example, a database may restrict access for medical records to a specific database user, but each record might only be intended to be accessible to the patient and the patient's doctor.
- Architecture and Design: Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. For example, consider using authorization frameworks such as the JAAS Authorization Framework [REF-233] and the OWASP ESAPI Access Control feature [REF-45].
- Architecture and Design: For web applications, make sure that the access control mechanism is enforced correctly at the server side on every page. Users should not be able to access any unauthorized functionality or information by simply requesting direct access to that page. One way to do this is to ensure that all pages containing sensitive information are not cached, and that all such pages restrict access to requests that are accompanied by an active and authenticated session token associated with a user who has the required permissions to access that page.
- System Configuration, Installation: Use the access control capabilities of your operating system and server environment and define your access control lists accordingly. Use a "default deny" policy when defining these ACLs.
References
Advisories
Packages
Other links
Timeline
- Published
- Last updated by the source
- Latest EPSS score
Related advisories
| Advisory | Severity | Why it's related |
|---|---|---|
| GHSA-79gf-7frw-68m9 Kyverno's NamespacedGeneratingPolicy generator.apply() namespace argument unvalidated -- background controller creates RoleBindings in any namespace including kube-system | Critical | Also affects github.com/kyverno/kyverno |
| GHSA-fpjq-c37h-cqcv Kyverno Controller Denial of Service via forEach Mutation Panic | High | Also affects github.com/kyverno/kyverno |
| GHSA-8wfp-579w-6r25 Kyverno apiCall automatically forwards ServiceAccount token to external endpoints (credential leak) | High | Also affects github.com/kyverno/kyverno |
| GHSA-f9g8-6ppc-pqq4 Kyverno: ServiceAccount token leaked to external servers via apiCall service URL | Critical | Also affects github.com/kyverno/kyverno |
| GHSA-cvq5-hhx3-f99p Kyverno: Cross-Namespace Read Bypasses RBAC Isolation (CVE-2026-22039 Incomplete Fix) | High | Also affects github.com/kyverno/kyverno |
| GHSA-q93q-v844-jrqp kyverno apicall servicecall implicit bearer token injection leaks kyverno serviceaccount token | High | Also affects github.com/kyverno/kyverno |
| GHSA-fmqp-4wfc-w3v7 Kyverno APICall SSRF Vulnerability Leading to Multi-Tenant Isolation Breach | Medium | Also affects github.com/kyverno/kyverno |
| GHSA-qr4g-8hrp-c4rw Kyverno has unrestricted outbound requests in Kyverno apiCall enabling SSRF | High | Also affects github.com/kyverno/kyverno |
MergeHarbor checks every repository's dependencies against this database, ranks what matters by exploitability and reachability, routes it to the owning team and opens the fix pull request.
Check your repos with MergeHarbor