Vulnerabilities in pkg:npm/pepr

PACKAGE
Advisory Identifier: GHSA-w54x-r83c-x79q
Advisory Summary

CVE-2026-23634 is a LOW (CVSS 0.0) pepr has overly permissive rbac vulnerability (CWE-272: Least Privilege Violation) affecting Pepr libraries in the npm ecosystem. The issue involves pepr has overly permissive rbac clusterrole in admin mode. Remediation is available by upgrading affected packages to version 1.0.5.

1 Known Advisory Record(s)
Package Vulnerability Intelligence

pkg:npm/pepr

1 Known Advisory Record(s)

Vulnerability advisories affecting package pkg:npm/pepr. Select an advisory below to view technical details or fixes.

Advisory ID CVE / NVD Severity Summary
GHSA-w54x-r83c-x79q CVE-2026-23634 LOW Pepr Has Overly Permissive RBAC ClusterRole in Admin Mode

CVE-2026-23634 at a Glance

CVE Identifier CVE-2026-23634
GHSA Identifier GHSA-w54x-r83c-x79q
Severity LOW
CVSS v3.1 Base Score 0.0
CWE Classification CWE-272: Least Privilege Violation
Affected Product Pepr
Package Ecosystem npm
Published Date
Last Updated

Security Impact

CVSS: 0.0

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:N).

Attack Vector Network (AV:N)
Attack Complexity Low (AC:L)
Privileges Required None (PR:N)
User Interaction None (UI:N)
Scope Unchanged (S:U)
Confidentiality None (C:N)
Integrity None (I:N)
Availability None (A:N)

How to Fix CVE-2026-23634

To remediate this vulnerability, upgrade all affected Pepr dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

pepr fixed: 1.0.5
npm install pepr@1.0.5
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release:

npm ls pepr

How to Check if You Are Affected

To determine whether your Node.js application is affected by CVE-2026-23634, inspect your project dependencies using npm:

npm ls pepr

Analyze the terminal output to locate any version of Pepr in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 1.0.5), your application is affected.

Note: The npm ls pepr command inspects dependencies declared in your package.json and lockfile; it does not perform automated runtime dynamic scanning.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-272: Least Privilege Violation, where the elevated privilege level required to perform operations such as chroot() should be dropped immediately after the operation is performed. In Pepr, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

Severity: LOW Target: /workspace/pepr/src/lib/assets/rbac.ts Endpoint: Kubernetes RBAC configuration Method: Deployment ## Response / Rationale Pepr defaults to `rbacMode: "admin"` because the initial experience is designed to be frictionless for new users. This mode ensures that users can deploy and run the default `hello-pepr.ts` module without needing to understand or pre-configure RBAC rules. It’s important to note that `hello-pepr.ts` is intended strictly as a demo to showcase Pepr features and workflow. It is not intended for production use, and the documentation explicitly calls out that admin RBAC should not be used in production environments. That said, if a user skips the documentation and does not review the `npx pepr build` options, they could deploy a module with broader privileges than necessary. We consider this low severity because Pepr is a framework: the module author is ultimately responsible for selecting the appropriate RBAC scope for their module and environment as each module has different RBAC needs and requirements. Our security focus is on ensuring the Pepr controller and runtime components operate securely within Kubernetes, while still allowing developers the flexibility to build modules with the access they require. In order to fix this we will warn the user in logs that the default `ClusterRole` is `cluster-admin` and that it is not recommended for production. ## How this can be exploited This is not an inherently exploitable CVE in the traditional sense. It is being flagged because Pepr defaults to a cluster-admin RBAC configuration and does not explicitly force or enforce least-privilege guidance for module authors. The default behavior exists to make the “getting started” experience smooth: new users can experiment with Pepr and create resources dynamically without needing to pre-configure RBAC. Remediation: scope RBAC appropriately before deploying to production. Running: ```bash npx pepr build --rbac-mode=scoped ``` generates the minimum RBAC required for the controller/informer to watch resources. Any additional permissions must be added based on the specific Kubernetes resources and CRUD operations performed by the module

CVE-2026-23634 Affected Pepr Versions

1 component(s)
Fixed Versions:
1.0.5
Product / Package Ecosystem Affected Versions Fixed Version
pepr
npm
< 1.0.5
1.0.5

References

Frequently Asked Questions

What is CVE-2026-23634?
CVE-2026-23634 is a security vulnerability in Pepr involving Pepr Has Overly Permissive RBAC ClusterRole in Admin Mode under CWE-272: Least Privilege Violation.
Which Pepr versions are affected?
Affected versions include releases prior to 1.0.5 across affected packages: pepr.
What version fixes CVE-2026-23634?
Upgrading to 1.0.5 (or the latest patched release for your respective branch) resolves the vulnerability.
Is pepr affected?
Yes, pepr is affected in releases prior to 1.0.5. Upgrade your dependency to 1.0.5 or later.
What is the CVSS score of CVE-2026-23634?
CVE-2026-23634 has a CVSS v3.1 base score of 0.0 (LOW) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:N.
What CWE is associated with CVE-2026-23634?
CVE-2026-23634 is classified under CWE-272: Least Privilege Violation (The elevated privilege level required to perform operations such as chroot() should be dropped immediately after the operation is performed.).
How can I check npm dependencies for CVE-2026-23634?
Run the dependency tree command: 'npm ls pepr'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-w54x-r83c-x79q",
  "modified" : "2026-01-16T21:56:18Z",
  "published" : "2026-01-15T20:14:31Z",
  "aliases" : [ "CVE-2026-23634" ],
  "summary" : "Pepr Has Overly Permissive RBAC ClusterRole in Admin Mode",
  "details" : "Severity: LOW\nTarget: /workspace/pepr/src/lib/assets/rbac.ts\nEndpoint: Kubernetes RBAC configuration\nMethod: Deployment\n\n## Response / Rationale\nPepr defaults to `rbacMode: \"admin\"` because the initial experience is designed to be frictionless for new users. This mode ensures that users can deploy and run the default `hello-pepr.ts` module without needing to understand or pre-configure RBAC rules.\n\nIt’s important to note that `hello-pepr.ts` is intended strictly as a demo to showcase Pepr features and workflow. It is not intended for production use, and the documentation explicitly calls out that admin RBAC should not be used in production environments.\n\nThat said, if a user skips the documentation and does not review the `npx pepr build` options, they could deploy a module with broader privileges than necessary.\n\nWe consider this low severity because Pepr is a framework: the module author is ultimately responsible for selecting the appropriate RBAC scope for their module and environment as each module has different RBAC needs and requirements. \n\nOur security focus is on ensuring the Pepr controller and runtime components operate securely within Kubernetes, while still allowing developers the flexibility to build modules with the access they require.\n\nIn order to fix this we will warn the user in logs that the default `ClusterRole` is `cluster-admin` and that it is not recommended for production.\n\n## How this can be exploited\n\nThis is not an inherently exploitable CVE in the traditional sense. It is being flagged because Pepr defaults to a cluster-admin RBAC configuration and does not explicitly force or enforce least-privilege guidance for module authors.\n\nThe default behavior exists to make the “getting started” experience smooth: new users can experiment with Pepr and create resources dynamically without needing to pre-configure RBAC.\n\nRemediation: scope RBAC appropriately before deploying to production. Running:\n\n```bash\nnpx pepr build --rbac-mode=scoped\n```\n\ngenerates the minimum RBAC required for the controller/informer to watch resources. Any additional permissions must be added based on the specific Kubernetes resources and CRUD operations performed by the module",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:N"
  }, {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:U"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "npm",
      "name" : "pepr"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "1.0.5"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/defenseunicorns/pepr/security/advisories/GHSA-w54x-r83c-x79q"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-23634"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/defenseunicorns/pepr/pull/2883"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/defenseunicorns/pepr/commit/d4675a662b8602fcde7e4bf603432f2f133b1fd1"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/defenseunicorns/pepr"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/defenseunicorns/pepr/releases/tag/v1.0.5"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-272", "CWE-276" ],
    "severity" : "LOW",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-01-15T20:14:31Z",
    "nvd_published_at" : "2026-01-16T20:15:49Z"
  }
}